Macellum of Pozzuoli
Encyclopedia
The Macellum of Pozzuoli was the macellum
or market building of the Roman colony
of Puteoli, now known as Pozzuoli
. When first excavated in the 18th century, the discovery of a statue of Serapis
led to the building being mis-identified as the city's serapeum
or Temple of Serapis.
A band of borings or Gastrochaenolites
left by marine Lithophaga
bivalve molluscs on three standing marble columns indicated that these columns had remained upright over centuries while the site sank below sea level, then re-emerged. This puzzling feature was the subject of debate in early geology
, and eventually led to the identification of bradyseism
in the area, showing that the Earth's crust could be subject to gradual movement without destructive earthquake
s.
, was integrated into the Roman Empire
as the city of Puteoli in 194 BC. The macellum
or food market was built between the late first and early second century AD, and restored during the third century AD under the Severan dynasty
.
The building was in the form of an arcaded square courtyard, surrounded by two-storey buildings. Shops lined the marble floored colonnade forming an arcade with 34 grey granite columns. The main entrance and vestibule were positioned on a main axis, which lined up across a tholos
in the centre of the square to the exedra
for worship which had a portico
formed by four large cipollino marble
columns. The exedra had three niches
for statues of divinities giving protection to the market, including the sculpture of Serapis
. The tholos in the centre of the square was a circular building standing on a podium reached by four symmetrically placed access stairways, with sixteen African marble columns supporting a domed vault. Marine animals decorated friezes around the base of the tholos. The courtyard had four secondary entrances on its longer sides, with latrines in the corners of the colonnade and four (probable) taberna
e with their own external entrances as well as access from the arcade.
of Naples
had excavations carried out between 1750 and 1756, exposing the three large cipollino marble columns which gave the site its name of the "three column vineyard". It attracted visits from antiquarians, among them William Hamilton
whose Campi Phlegraei of 1776 showed a distant view of the buildings dry above sea level, and John Soane
who "Went to the Temple of Jupiter Serapis" on 1 January 1779 and made rough sketches, as well as a plan of the complex, possibly copied from another drawing.
In 1798 Scipione Breislak
described his fieldwork at the site in his Topografia fisica della Campania, and theorised about changes in sea level around that coast. He argued that the evidence did not support the suggestion of falling sea levels worldwide, but thought seismic explanations
were inadequate as earthquake
s notoriously shook buildings until they collapsed, and the columns were still standing. He concluded that there must have been undetectable movement of the crust of the Earth, but recognised that this was unsatisfactory as the cause could not be seen. In 1802 John Playfair
, in his Illustrations of the Huttonian Theory of the Earth, used Breislak's descriptions to support James Hutton
's ideas of slow changes, attributing the differing heights of water around the columns to "oscillations" in the level of the land.
Between 1806 and 1818 further excavations exposed the whole of the "Serapeum" or "Temple of Serapis". The excavations lost stratigraphic
information in the deposits which had buried the building, but the band of borings or Gastrochaenolites
left by marine Lithophaga
bivalves on the three standing marble columns provided a good record of relative sea level variation.
The antiquarian Andrea di Jorio studied the ruins, and in 1817 published a guidebook to the Phlegraean Fields, with a map of the area which had many hot springs and volcanic craters as well as antiquarian sites including the supposed Temple. By this time the pavement was flooded by the sea, indicating a slight lowering of the land level. In 1820, he published a study of his Ricerche sul Tempio di Serapide, in Puzzuoli, including an illustration based on a drawing by John Izard Middleton
showing the three columns with the bands affected by molluscs.
In 1819 Giovanni Battista Brocchi
proposed that the columns below the bands had been protected from the molluscs by being buried in silt or volcanic ash. The first volume of Veränderungen der Erdoberfläche by Karl Ernst Adolf von Hoff
, published in 1822, included an account of the ruins as demonstrating relative changes in land and sea level. Hoff's second volume of 1824 reviewed how earthquakes might have caused this, and mentioned Jorio's study. Hoff's account motivated Johann Wolfgang von Goethe
to publish his own idea, coined when he visited the site in 1787. In Goethe's 1823 Architektonisch-naturhistorisches Problem, he suggested that silt or ash had partially buried the columns and at the same time held back water forming a lagoon above sea level. Robert Jameson
had this paper translated for his Edinburgh
journal, to oppose Playfair's views. Other naturalists thought this unlikely, as the fresh water lagoon would not have supported marine molluscs, and the sea was by then higher than at the time of Goethe's visit.
In his 1826 book A Description of Active and Extinct Volcanoes, Charles Daubeny
dismissed the implied sinking of the land by 30 feet (9.1 m) followed by almost as great a rise as unlikely, since "it is probable that not a single pillar of the temple would now retain its erect posture to attest the reality of these convulsions". Daubeny also doubted changing sea levels, so concluded that the bands of holes bored by molluscs must be due to local damming of water around the buildings.
Charles Lyell
's Principles of Geology
of 1830 featured as its frontispiece a replication of di Jorio's illustration of the columns (shown above), and a detailed section discussing their significance. He strongly contested Daubeny's argument, and instead proposed slow and steady geological forces. Lyell wrote "That buildings should have been submerged, and afterwards upheaved, without being entirely reduced to a heap of ruins, will appear no anomaly, when we recollect that in the year 1819, when the delta of the Indus sank down, the houses within the fort of Sindree subsided beneath the waves without being overthrown." In 1832 the young Charles Darwin
used Lyell's methods at the first landfall of the Beagle survey voyage
, while considering evidence of land rising up at St. Jago
. In his journal, Darwin dismissed Daubeny's argument, and wrote that he felt "sure at St Jago in some places a town might have been raised without injuring a house."
Charles Babbage
carried out a detailed survey of the ruins in 1828 and his Observations on the Temple of Serapis at Pozzuoli, near Naples were published in 1847. In some of the rooms of the macellum Babbage found a dark brownish encrustation of salts, and a thicker encrustation up to a height of about 9 feet (2.7 m) from floor level. These have been interpreted as showing that as the building lowered, a little lake formed and allowed water to enter the building without there being a direct connection to the sea, then at a later stage the land subsided to the point where sea water came in, and the Lithophaga started drilling holes in the masonry up to 19 feet (5.8 m) from floor level.
The identification of the building as a macellum
or marketplace rather than a temple was made by Charles Dubois, who published a detailed account of the ruins of Pozzuoli in his Pouzzoles antiques. Histoire et topographie of 1907.
and has been subject to repeated "slow earthquakes" or bradyseism
of this shallow caldera resulting in relatively slow subsidence over long periods, drowning the ruin, punctuated by periods of relatively rapid uplift that caused it to re-emerge. After a long subsidence through Roman times, there was a period of uplift in the Middle Ages
around AD 700 to 800, then after more subsidence the land rose again from around 1500 up to the last eruption in 1538. The land again subsided gradually, then between 1969 and 1973 the land rose by about 1.7 metres (5.6 ft). Over the following decade there was a little subsidence, then between 1982 and 1994 there was uplift of almost 2 metres (6.6 ft). Concerns about risks of earthquake damage and possible eruption led to temporary evacuation of the city of Pozzuoli
. Detailed measurements indicated that the caldera deformation formed a nearly circular lens centred near Pozzuoli. Various models have been produced to find mechanisms explaining this pattern.
Macellum
A macellum is an ancient Roman indoor market building that sold mostly provisions . The building normally sat alongside the forum and basilica, providing a place in which a market could be held...
or market building of the Roman colony
Colonia (Roman)
A Roman colonia was originally a Roman outpost established in conquered territory to secure it. Eventually, however, the term came to denote the highest status of Roman city.-History:...
of Puteoli, now known as Pozzuoli
Pozzuoli
Pozzuoli is a city and comune of the province of Naples, in the Italian region of Campania. It is the main city of the Phlegrean peninsula.-History:Pozzuoli began as the Greek colony of Dicaearchia...
. When first excavated in the 18th century, the discovery of a statue of Serapis
Serapis
Serapis or Sarapis is a Graeco-Egyptian name of God. Serapis was devised during the 3rd century BC on the orders of Ptolemy I of Egypt as a means to unify the Greeks and Egyptians in his realm. The god was depicted as Greek in appearance, but with Egyptian trappings, and combined iconography...
led to the building being mis-identified as the city's serapeum
Serapeum
A serapeum is a temple or other religious institution dedicated to the syncretic Hellenistic-Egyptian god Serapis, who combined aspects of Osiris and Apis in a humanized form that was accepted by the Ptolemaic Greeks of Alexandria...
or Temple of Serapis.
A band of borings or Gastrochaenolites
Gastrochaenolites
Gastrochaenolites is a trace fossil formed as a clavate boring in a hard substrate such as a shell, rock or carbonate hardground. The aperture of the boring is narrower than the main chamber and may be circular, oval, or dumb-bell shaped...
left by marine Lithophaga
Lithophaga
Lithophaga, the date mussels, are a genus of medium-sized marine bivalve molluscs in the family Mytilidae.The shells of species in this genus are long and narrow with parallel sides. The animals bore into stone or coral rock with the help of pallial gland secretions, hence the systematic name...
bivalve molluscs on three standing marble columns indicated that these columns had remained upright over centuries while the site sank below sea level, then re-emerged. This puzzling feature was the subject of debate in early geology
History of geology
The history of geology is concerned with the development of the natural science of geology. Geology is the scientific study of the origin, history, and structure of the Earth. Throughout the ages geology provides essential theories and data that shape how society conceptualizes the...
, and eventually led to the identification of bradyseism
Bradyseism
Bradyseism is the gradual uplift or descent of part of the Earth's surface caused by the filling or emptying of an underground magma chamber and/or hydrothermal activity, particularly in volcanic calderas...
in the area, showing that the Earth's crust could be subject to gradual movement without destructive earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s.
Roman origins
The city of Dicearchia, founded by Greek refugees escaping dictatorship on SamosSamoš
Samoš is a village in Serbia. It is situated in the Kovačica municipality, in the South Banat District, Vojvodina province. The village has a Serb ethnic majority and its population numbering 1,247 people .-See also:...
, was integrated into the Roman Empire
Roman Empire
The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....
as the city of Puteoli in 194 BC. The macellum
Macellum
A macellum is an ancient Roman indoor market building that sold mostly provisions . The building normally sat alongside the forum and basilica, providing a place in which a market could be held...
or food market was built between the late first and early second century AD, and restored during the third century AD under the Severan dynasty
Severan dynasty
The Severan dynasty was a Roman imperial dynasty, which ruled the Roman Empire between 193 and 235. The dynasty was founded by the Roman general Septimius Severus, who rose to power during the civil war of 193, known as the Year of the Five Emperors....
.
The building was in the form of an arcaded square courtyard, surrounded by two-storey buildings. Shops lined the marble floored colonnade forming an arcade with 34 grey granite columns. The main entrance and vestibule were positioned on a main axis, which lined up across a tholos
Tholos (Ancient Rome)
A tholos is an ancient Roman feature found in the macellum. It has been suggested that the tholos, well provided with water and drains, was where fish were sold, although other uses for the central tholos have been suggested, such as the place where official weights and measures were held for...
in the centre of the square to the exedra
Exedra
In architecture, an exedra is a semicircular recess or plinth, often crowned by a semi-dome, which is sometimes set into a building's facade. The original Greek sense was applied to a room that opened onto a stoa, ringed with curved high-backed stone benches, a suitable place for a philosophical...
for worship which had a portico
Portico
A portico is a porch leading to the entrance of a building, or extended as a colonnade, with a roof structure over a walkway, supported by columns or enclosed by walls...
formed by four large cipollino marble
Cipollino marble
Cipollino marble was a variety of marble used by the ancient Greeks and Romans, whose Latin term for it was "marmor carystium" . It was quarried in several locations on the south-west coast of the island of Euboea in Greece, between the modern-day cities of Styra and Karystos...
columns. The exedra had three niches
Niche (architecture)
A niche in classical architecture is an exedra or an apse that has been reduced in size, retaining the half-dome heading usual for an apse. Nero's Domus Aurea was the first semi-private dwelling that possessed rooms that were given richly varied floor plans, shaped with niches and exedras;...
for statues of divinities giving protection to the market, including the sculpture of Serapis
Serapis
Serapis or Sarapis is a Graeco-Egyptian name of God. Serapis was devised during the 3rd century BC on the orders of Ptolemy I of Egypt as a means to unify the Greeks and Egyptians in his realm. The god was depicted as Greek in appearance, but with Egyptian trappings, and combined iconography...
. The tholos in the centre of the square was a circular building standing on a podium reached by four symmetrically placed access stairways, with sixteen African marble columns supporting a domed vault. Marine animals decorated friezes around the base of the tholos. The courtyard had four secondary entrances on its longer sides, with latrines in the corners of the colonnade and four (probable) taberna
Taberna
A taberna was a single room shop covered by a barrel vault within great indoor markets of ancient Rome. Each taberna had a window above it to let light into a wooden attic for storage and had a wide doorway....
e with their own external entrances as well as access from the arcade.
Excavation and influence on geology
King CharlesCharles III of Spain
Charles III was the King of Spain and the Spanish Indies from 1759 to 1788. He was the eldest son of Philip V of Spain and his second wife, the Princess Elisabeth Farnese...
of Naples
Naples
Naples is a city in Southern Italy, situated on the country's west coast by the Gulf of Naples. Lying between two notable volcanic regions, Mount Vesuvius and the Phlegraean Fields, it is the capital of the region of Campania and of the province of Naples...
had excavations carried out between 1750 and 1756, exposing the three large cipollino marble columns which gave the site its name of the "three column vineyard". It attracted visits from antiquarians, among them William Hamilton
William Hamilton (diplomat)
Sir William Hamilton KB, PC, FRS was a Scottish diplomat, antiquarian, archaeologist and vulcanologist. After a short period as a Member of Parliament, he served as British Ambassador to the Kingdom of Naples from 1764 to 1800...
whose Campi Phlegraei of 1776 showed a distant view of the buildings dry above sea level, and John Soane
John Soane
Sir John Soane, RA was an English architect who specialised in the Neo-Classical style. His architectural works are distinguished by their clean lines, massing of simple form, decisive detailing, careful proportions and skilful use of light sources...
who "Went to the Temple of Jupiter Serapis" on 1 January 1779 and made rough sketches, as well as a plan of the complex, possibly copied from another drawing.
In 1798 Scipione Breislak
Scipione Breislak
Scipione Breislak , Italian geologist of German parentage, was born in Rome in 1748. He distinguished himself as professor of mathematical and mechanical philosophy in the college of Ragusa; but after residing there for several years he returned to his native city, where he became a professor in...
described his fieldwork at the site in his Topografia fisica della Campania, and theorised about changes in sea level around that coast. He argued that the evidence did not support the suggestion of falling sea levels worldwide, but thought seismic explanations
Seismology
Seismology is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies. The field also includes studies of earthquake effects, such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, oceanic,...
were inadequate as earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s notoriously shook buildings until they collapsed, and the columns were still standing. He concluded that there must have been undetectable movement of the crust of the Earth, but recognised that this was unsatisfactory as the cause could not be seen. In 1802 John Playfair
John Playfair
John Playfair FRSE, FRS was a Scottish scientist and mathematician, and a professor of natural philosophy at the University of Edinburgh. He is perhaps best known for his book Illustrations of the Huttonian Theory of the Earth , which summarized the work of James Hutton...
, in his Illustrations of the Huttonian Theory of the Earth, used Breislak's descriptions to support James Hutton
James Hutton
James Hutton was a Scottish physician, geologist, naturalist, chemical manufacturer and experimental agriculturalist. He is considered the father of modern geology...
's ideas of slow changes, attributing the differing heights of water around the columns to "oscillations" in the level of the land.
Between 1806 and 1818 further excavations exposed the whole of the "Serapeum" or "Temple of Serapis". The excavations lost stratigraphic
Stratigraphy
Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary and layered volcanic rocks....
information in the deposits which had buried the building, but the band of borings or Gastrochaenolites
Gastrochaenolites
Gastrochaenolites is a trace fossil formed as a clavate boring in a hard substrate such as a shell, rock or carbonate hardground. The aperture of the boring is narrower than the main chamber and may be circular, oval, or dumb-bell shaped...
left by marine Lithophaga
Lithophaga
Lithophaga, the date mussels, are a genus of medium-sized marine bivalve molluscs in the family Mytilidae.The shells of species in this genus are long and narrow with parallel sides. The animals bore into stone or coral rock with the help of pallial gland secretions, hence the systematic name...
bivalves on the three standing marble columns provided a good record of relative sea level variation.
The antiquarian Andrea di Jorio studied the ruins, and in 1817 published a guidebook to the Phlegraean Fields, with a map of the area which had many hot springs and volcanic craters as well as antiquarian sites including the supposed Temple. By this time the pavement was flooded by the sea, indicating a slight lowering of the land level. In 1820, he published a study of his Ricerche sul Tempio di Serapide, in Puzzuoli, including an illustration based on a drawing by John Izard Middleton
John Izard Middleton
John Izard Middleton was an American archeologist and artist.Born just outside of Charleston, South Carolina, he was the son of Mary Izard and Arthur Middleton . He was dubbed "the first American Classical Archaeologist" by Charles Eliot Norton. In 1810 he married Eliza Augusta Falconet, the...
showing the three columns with the bands affected by molluscs.
In 1819 Giovanni Battista Brocchi
Giovanni Battista Brocchi
Giovanni Battista Brocchi was an Italian naturalist, mineralogist and geologist.He was born in Bassano del Grappa, Italy, and studied jurisprudence at the University of Padova, but his attention was turned to mineralogy and botany...
proposed that the columns below the bands had been protected from the molluscs by being buried in silt or volcanic ash. The first volume of Veränderungen der Erdoberfläche by Karl Ernst Adolf von Hoff
Karl Ernst Adolf von Hoff
Karl Ernst Adolf von Hoff was a German natural historian and geologist.After studying law, physics and natural history, in 1791 he was appointed to a diplomatic post by Ernest II, Duke of Saxe-Gotha-Altenburg...
, published in 1822, included an account of the ruins as demonstrating relative changes in land and sea level. Hoff's second volume of 1824 reviewed how earthquakes might have caused this, and mentioned Jorio's study. Hoff's account motivated Johann Wolfgang von Goethe
Johann Wolfgang von Goethe
Johann Wolfgang von Goethe was a German writer, pictorial artist, biologist, theoretical physicist, and polymath. He is considered the supreme genius of modern German literature. His works span the fields of poetry, drama, prose, philosophy, and science. His Faust has been called the greatest long...
to publish his own idea, coined when he visited the site in 1787. In Goethe's 1823 Architektonisch-naturhistorisches Problem, he suggested that silt or ash had partially buried the columns and at the same time held back water forming a lagoon above sea level. Robert Jameson
Robert Jameson
thumb|Robert JamesonProfessor Robert Jameson, FRS FRSE was a Scottish naturalist and mineralogist.As Regius Professor at the University of Edinburgh for fifty years, Jameson is notable for his advanced scholarship in natural history, his superb museum collection, and for his tuition of Charles...
had this paper translated for his Edinburgh
Edinburgh
Edinburgh is the capital city of Scotland, the second largest city in Scotland, and the eighth most populous in the United Kingdom. The City of Edinburgh Council governs one of Scotland's 32 local government council areas. The council area includes urban Edinburgh and a rural area...
journal, to oppose Playfair's views. Other naturalists thought this unlikely, as the fresh water lagoon would not have supported marine molluscs, and the sea was by then higher than at the time of Goethe's visit.
In his 1826 book A Description of Active and Extinct Volcanoes, Charles Daubeny
Charles Daubeny
Charles Giles Bridle Daubeny was an English chemist, botanist and geologist.Daubeny was born at Stratton near Cirencester in Gloucestershire, the son of the Rev. James Daubeny. He studied at Magdalen College, Oxford under Dr. John Kidd...
dismissed the implied sinking of the land by 30 feet (9.1 m) followed by almost as great a rise as unlikely, since "it is probable that not a single pillar of the temple would now retain its erect posture to attest the reality of these convulsions". Daubeny also doubted changing sea levels, so concluded that the bands of holes bored by molluscs must be due to local damming of water around the buildings.
Charles Lyell
Charles Lyell
Sir Charles Lyell, 1st Baronet, Kt FRS was a British lawyer and the foremost geologist of his day. He is best known as the author of Principles of Geology, which popularised James Hutton's concepts of uniformitarianism – the idea that the earth was shaped by slow-moving forces still in operation...
's Principles of Geology
Principles of Geology
Principles of Geology, being an attempt to explain the former changes of the Earth's surface, by reference to causes now in operation, is a book by the Scottish geologist Charles Lyell....
of 1830 featured as its frontispiece a replication of di Jorio's illustration of the columns (shown above), and a detailed section discussing their significance. He strongly contested Daubeny's argument, and instead proposed slow and steady geological forces. Lyell wrote "That buildings should have been submerged, and afterwards upheaved, without being entirely reduced to a heap of ruins, will appear no anomaly, when we recollect that in the year 1819, when the delta of the Indus sank down, the houses within the fort of Sindree subsided beneath the waves without being overthrown." In 1832 the young Charles Darwin
Charles Darwin
Charles Robert Darwin FRS was an English naturalist. He established that all species of life have descended over time from common ancestry, and proposed the scientific theory that this branching pattern of evolution resulted from a process that he called natural selection.He published his theory...
used Lyell's methods at the first landfall of the Beagle survey voyage
Second voyage of HMS Beagle
The second voyage of HMS Beagle, from 27 December 1831 to 2 October 1836, was the second survey expedition of HMS Beagle, under captain Robert FitzRoy who had taken over command of the ship on its first voyage after her previous captain committed suicide...
, while considering evidence of land rising up at St. Jago
Santiago, Cape Verde
Santiago , or Santiagu in Cape Verdean Creole, is the largest island of Cape Verde, its most important agricultural centre and home to half the nation’s population. At the time of Darwin's voyage it was called St. Jago....
. In his journal, Darwin dismissed Daubeny's argument, and wrote that he felt "sure at St Jago in some places a town might have been raised without injuring a house."
Charles Babbage
Charles Babbage
Charles Babbage, FRS was an English mathematician, philosopher, inventor and mechanical engineer who originated the concept of a programmable computer...
carried out a detailed survey of the ruins in 1828 and his Observations on the Temple of Serapis at Pozzuoli, near Naples were published in 1847. In some of the rooms of the macellum Babbage found a dark brownish encrustation of salts, and a thicker encrustation up to a height of about 9 feet (2.7 m) from floor level. These have been interpreted as showing that as the building lowered, a little lake formed and allowed water to enter the building without there being a direct connection to the sea, then at a later stage the land subsided to the point where sea water came in, and the Lithophaga started drilling holes in the masonry up to 19 feet (5.8 m) from floor level.
The identification of the building as a macellum
Macellum
A macellum is an ancient Roman indoor market building that sold mostly provisions . The building normally sat alongside the forum and basilica, providing a place in which a market could be held...
or marketplace rather than a temple was made by Charles Dubois, who published a detailed account of the ruins of Pozzuoli in his Pouzzoles antiques. Histoire et topographie of 1907.
Modern investigations
More recent investigations of the vertical movements have shown that the site is near the centre of the Campi Flegrei (Phlegraean Fields) calderaCaldera
A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...
and has been subject to repeated "slow earthquakes" or bradyseism
Bradyseism
Bradyseism is the gradual uplift or descent of part of the Earth's surface caused by the filling or emptying of an underground magma chamber and/or hydrothermal activity, particularly in volcanic calderas...
of this shallow caldera resulting in relatively slow subsidence over long periods, drowning the ruin, punctuated by periods of relatively rapid uplift that caused it to re-emerge. After a long subsidence through Roman times, there was a period of uplift in the Middle Ages
Middle Ages
The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...
around AD 700 to 800, then after more subsidence the land rose again from around 1500 up to the last eruption in 1538. The land again subsided gradually, then between 1969 and 1973 the land rose by about 1.7 metres (5.6 ft). Over the following decade there was a little subsidence, then between 1982 and 1994 there was uplift of almost 2 metres (6.6 ft). Concerns about risks of earthquake damage and possible eruption led to temporary evacuation of the city of Pozzuoli
Pozzuoli
Pozzuoli is a city and comune of the province of Naples, in the Italian region of Campania. It is the main city of the Phlegrean peninsula.-History:Pozzuoli began as the Greek colony of Dicaearchia...
. Detailed measurements indicated that the caldera deformation formed a nearly circular lens centred near Pozzuoli. Various models have been produced to find mechanisms explaining this pattern.