Fan vault
Encyclopedia
Vault (architecture)
A Vault is an architectural term for an arched form used to provide a space with a ceiling or roof. The parts of a vault exert lateral thrust that require a counter resistance. When vaults are built underground, the ground gives all the resistance required...
used in the Gothic style, in which the ribs are all of the same curve and spaced equidistantly, in a manner resembling a fan
Fan (implement)
A hand-held fan is an implement used to induce an airflow for the purpose of cooling or refreshing oneself. Any broad, flat surface waved back-and-forth will create a small airflow and therefore can be considered a rudimentary fan...
. The initiation and propagation of this design element is strongly associated with England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
.
The earliest example, dating from about the year 1351, may be seen in the cloisters of Gloucester Cathedral
Gloucester Cathedral
Gloucester Cathedral, or the Cathedral Church of St Peter and the Holy and Indivisible Trinity, in Gloucester, England, stands in the north of the city near the river. It originated in 678 or 679 with the foundation of an abbey dedicated to Saint Peter .-Foundations:The foundations of the present...
. The largest fan vault in the world can be found in the chapel of King's College, Cambridge
King's College Chapel, Cambridge
King's College Chapel is the chapel to King's College of the University of Cambridge, and is one of the finest examples of late Gothic English architecture, while its early Renaissance rood screen separating the nave and chancel, erected in 1532-36 in a striking contrast of style, has been called...
.
The fan vault is peculiar to England. The lierne
Lierne (vault)
A Lierne in Gothic rib vaulting is an architectural term for a tertiary rib spanning between two other ribs, instead of from a springer, or to the central boss...
vault of the cathedral of Barbastro
Barbastro
Barbastro is a city in the Somontano county, province of Huesca, Spain...
in Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
closely resembles a fan vault, but it does not form a perfect conoid. Harvey (1978) suggests Catherine of Aragon
Catherine of Aragon
Catherine of Aragon , also known as Katherine or Katharine, was Queen consort of England as the first wife of King Henry VIII of England and Princess of Wales as the wife to Arthur, Prince of Wales...
as a possible source of English influence in Aragon
Aragon
Aragon is a modern autonomous community in Spain, coextensive with the medieval Kingdom of Aragon. Located in northeastern Spain, the Aragonese autonomous community comprises three provinces : Huesca, Zaragoza, and Teruel. Its capital is Zaragoza...
.
Birth of the fan vault
The fan vault is attributed to development in GloucesterGloucester
Gloucester is a city, district and county town of Gloucestershire in the South West region of England. Gloucester lies close to the Welsh border, and on the River Severn, approximately north-east of Bristol, and south-southwest of Birmingham....
between 1351 and 1377, with the earliest known surviving example being the east cloister walk of Gloucester Cathedral
Gloucester Cathedral
Gloucester Cathedral, or the Cathedral Church of St Peter and the Holy and Indivisible Trinity, in Gloucester, England, stands in the north of the city near the river. It originated in 678 or 679 with the foundation of an abbey dedicated to Saint Peter .-Foundations:The foundations of the present...
. Harvey (1978) hypothesises that the east cloister at Gloucester was finished under Thomas de Cambridge (Thomas de Cantebrugge) from Cambridge, Gloucestershire
Cambridge, Gloucestershire
Cambridge is a hamlet in the district of Stroud, in the county of Gloucestershire, England. It lies on the A38 road between Bristol and Gloucester, about three miles from Dursley....
, who left in 1364 to work on the chapter house
Chapter house
A chapter house or chapterhouse is a building or room attached to a cathedral or collegiate church in which meetings are held. They can also be found in medieval monasteries....
at Hereford Cathedral
Hereford Cathedral
The current Hereford Cathedral, located at Hereford in England, dates from 1079. Its most famous treasure is Mappa Mundi, a mediæval map of the world dating from the 13th century. The cathedral is a Grade I listed building.-Origins:...
(also thought to have been fan vaulted on the basis of a drawing by William Stukeley
William Stukeley
William Stukeley FRS, FRCP, FSA was an English antiquarian who pioneered the archaeological investigation of the prehistoric monuments of Stonehenge and Avebury, work for which he has been remembered as "probably... the most important of the early forerunners of the discipline of archaeology"...
). The other three parts of the cloister at Gloucester were begun in 1381, possibly under Robert Lesyngham.
Other examples of early fan vaults exist around Gloucester
Gloucester
Gloucester is a city, district and county town of Gloucestershire in the South West region of England. Gloucester lies close to the Welsh border, and on the River Severn, approximately north-east of Bristol, and south-southwest of Birmingham....
, implying the activity of several 14th century master masons in this region, who really created the fan vault and experimented with forms of its early use.
Structure
The ribs of a fan vault are of equal curvature and rotated at equal distances around a central (vertical) axis, forming the conoid shape which gives rise to the name. In between sequences of conoids, flat central spandrelSpandrel
A spandrel, less often spandril or splaundrel, is the space between two arches or between an arch and a rectangular enclosure....
s fill the space. According to Leedy (1980), the fan vault was developed in England (as opposed to France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
and other centres of gothic architecture) due to the manner in which English rib vault
Rib vault
The intersection of two or three barrel vaults produces a rib vault or ribbed vault when they are edged with an armature of piped masonry often carved in decorative patterns; compare groin vault, an older form of vault construction...
s were normally constructed. In an English rib vault, the courses are laid perpendicular to the rib while in France they are laid perpendicular to the wall.
List of buildings with fan vaulting
- Gloucester CathedralGloucester CathedralGloucester Cathedral, or the Cathedral Church of St Peter and the Holy and Indivisible Trinity, in Gloucester, England, stands in the north of the city near the river. It originated in 678 or 679 with the foundation of an abbey dedicated to Saint Peter .-Foundations:The foundations of the present...
, cloisters (Thomas de Cambridge) - King's College Chapel, CambridgeKing's College Chapel, CambridgeKing's College Chapel is the chapel to King's College of the University of Cambridge, and is one of the finest examples of late Gothic English architecture, while its early Renaissance rood screen separating the nave and chancel, erected in 1532-36 in a striking contrast of style, has been called...
, the world's largest fan vaulted structure (by William VertueWilliam VertueWilliam Vertue was an English architect specialising in Fan vault ceilings.Along with his brother Robert he was involved in the construction of the Tower of London , Bath Abbey, the Vertue brothers are reported as telling Bishop Oliver King the patron of the work that the vaulting "Ther shal be...
) - Henry VII's Lady Chapel, Westminster AbbeyWestminster AbbeyThe Collegiate Church of St Peter at Westminster, popularly known as Westminster Abbey, is a large, mainly Gothic church, in the City of Westminster, London, United Kingdom, located just to the west of the Palace of Westminster. It is the traditional place of coronation and burial site for English,...
, LondonLondonLondon is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
, England, 1503-1509 (with pendantsPendant vaultA pendant vault is a rare form of vault used in late Gothic architecture in which large decorative pendants hang from the vault at a distance from the walls...
, by William VertueWilliam VertueWilliam Vertue was an English architect specialising in Fan vault ceilings.Along with his brother Robert he was involved in the construction of the Tower of London , Bath Abbey, the Vertue brothers are reported as telling Bishop Oliver King the patron of the work that the vaulting "Ther shal be...
) - Bath AbbeyBath AbbeyThe Abbey Church of Saint Peter and Saint Paul, Bath, commonly known as Bath Abbey, is an Anglican parish church and a former Benedictine monastery in Bath, Somerset, England...
, SomersetSomersetThe ceremonial and non-metropolitan county of Somerset in South West England borders Bristol and Gloucestershire to the north, Wiltshire to the east, Dorset to the south-east, and Devon to the south-west. It is partly bounded to the north and west by the Bristol Channel and the estuary of the...
, England, nave and chancel (1860s restoration; originally by William VertueWilliam VertueWilliam Vertue was an English architect specialising in Fan vault ceilings.Along with his brother Robert he was involved in the construction of the Tower of London , Bath Abbey, the Vertue brothers are reported as telling Bishop Oliver King the patron of the work that the vaulting "Ther shal be...
) - St Stephen's cloisterCloisterA cloister is a rectangular open space surrounded by covered walks or open galleries, with open arcades on the inner side, running along the walls of buildings and forming a quadrangle or garth...
at the Palace of WestminsterPalace of WestminsterThe Palace of Westminster, also known as the Houses of Parliament or Westminster Palace, is the meeting place of the two houses of the Parliament of the United Kingdom—the House of Lords and the House of Commons...
(1529) - Christ Church, OxfordChrist Church, OxfordChrist Church or house of Christ, and thus sometimes known as The House), is one of the largest constituent colleges of the University of Oxford in England...
, staircase to the great hall - Convocation HouseConvocation HouseThe lower floor of the 1634–37 westward addition to the University of Oxford's Bodleian Library and Divinity School in Oxford, England, is known as Convocation House....
, OxfordOxfordThe city of Oxford is the county town of Oxfordshire, England. The city, made prominent by its medieval university, has a population of just under 165,000, with 153,900 living within the district boundary. It lies about 50 miles north-west of London. The rivers Cherwell and Thames run through... - University Church of St Mary the VirginUniversity Church of St Mary the VirginThe University Church of St Mary the Virgin is the largest of Oxford's parish churches and the centre from which the University of Oxford grew...
, OxfordOxfordThe city of Oxford is the county town of Oxfordshire, England. The city, made prominent by its medieval university, has a population of just under 165,000, with 153,900 living within the district boundary. It lies about 50 miles north-west of London. The rivers Cherwell and Thames run through...
, porch - St. George's Chapel, Windsor, crossing, Urswick chantry chapel
- Peterborough CathedralPeterborough CathedralPeterborough Cathedral, properly the Cathedral Church of St Peter, St Paul and St Andrew – also known as Saint Peter's Cathedral in the United Kingdom – is the seat of the Bishop of Peterborough, dedicated to Saint Peter, Saint Paul and Saint Andrew, whose statues look down from the...
, CambridgeshireCambridgeshireCambridgeshire is a county in England, bordering Lincolnshire to the north, Norfolk to the northeast, Suffolk to the east, Essex and Hertfordshire to the south, and Bedfordshire and Northamptonshire to the west...
, retrochoir - Eton College Chapel (the vault dates from 1958)
- Sherborne AbbeySherborne AbbeyThe Abbey Church of St Mary the Virgin at Sherborne in the English county of Dorset, is usually called Sherborne Abbey. It has been a Saxon cathedral , a Benedictine abbey and is now a parish church.- Cathedral :...
, nave (by William SmythWilliam Smyth (architect)William Smyth was an English gothic architect responsible for work including the fan vaults at Wells Cathedral, Sherborne Abbey and Milton Abbey. He may also have been the architect of Church of St Bartholomew, Crewkerne.-References:...
) - Milton AbbeyMilton AbbeyMilton Abbey School is a British independent school in the Dorset countryside. It has 227 pupils in six boarding Houses, called Athelstan, Bancks, Damer, Hambro, Middleton and Tregonwell. Founded in 1954, it welcomes boys from 13 to 16 years and is coeducational in the sixth form.The school has a...
, crossing (by William SmythWilliam Smyth (architect)William Smyth was an English gothic architect responsible for work including the fan vaults at Wells Cathedral, Sherborne Abbey and Milton Abbey. He may also have been the architect of Church of St Bartholomew, Crewkerne.-References:...
) - Canterbury CathedralCanterbury CathedralCanterbury Cathedral in Canterbury, Kent, is one of the oldest and most famous Christian structures in England and forms part of a World Heritage Site....
, crossing tower (by John WastellJohn WastellJohn Wastell was an English gothic architect responsible for Manchester Cathedral, parts of King's College Chapel, Cambridge, the crossing tower of Canterbury Cathedral, and the fan vaulted section of Peterborough Cathedral. He also worked on Bury St Edmunds Abbey....
), Henry VI's chantry chapel - Winchester CathedralWinchester CathedralWinchester Cathedral at Winchester in Hampshire is one of the largest cathedrals in England, with the longest nave and overall length of any Gothic cathedral in Europe...
, Beaufort and Waynflete chantry chapels - St Davids Cathedral, Trinity Chapel
- Tewkesbury AbbeyTewkesbury AbbeyThe Abbey of the Blessed Virgin Mary at Tewkesbury in the English county of Gloucestershire is the second largest parish church in the country and a former Benedictine monastery.-History:...
, cloister (only 1 bay remains) - Hampton Court PalaceHampton Court PalaceHampton Court Palace is a royal palace in the London Borough of Richmond upon Thames, Greater London; it has not been inhabited by the British royal family since the 18th century. The palace is located south west of Charing Cross and upstream of Central London on the River Thames...
, Great Gate and oriel window in the Great Hall - Church of St. John the Baptist, CirencesterChurch of St. John the Baptist, CirencesterThe Church of St. John the Baptist, Cirencester is a parish church in the Church of England in Cirencester.-History:The church is medieval. It is renowned for its perpendicular porch, fan vaults and merchants' tombs....
, porch and north chapel - St Andrew's Church, CullomptonCullomptonCullompton is a civil parish and town in Devon, England, locally known as Cully. It is miles north-north-east of Exeter and lies on the River Culm. In 2010 it had a population of 8,639 and is growing rapidly....
, south aisle - St Mary's Church, Ottery St MaryOttery St MaryOttery St Mary, known as "Ottery" , is a town in the East Devon district of Devon, England, on the River Otter, about ten miles east of Exeter on the B3174. It is part of a large civil parish of the same name, which also covers the villages of West Hill, Metcombe, Fairmile, Alfington, Tipton St...
, aisle - Dean's Chapel, Collegiate Church of St Mary, WarwickCollegiate Church of St Mary, WarwickThe Collegiate Church of St Mary is a Church of England parish church in the town of Warwick, England. It lies in the centre of the town just east of the market place. It is a member of the Greater Churches Group....
- Ely CathedralEly CathedralEly Cathedral is the principal church of the Diocese of Ely, in Cambridgeshire, England, and is the seat of the Bishop of Ely and a suffragan bishop, the Bishop of Huntingdon...
, Bishop AlcockJohn Alcock (bishop)-Biography:Alcock was born at Beverley in Yorkshire, son of Sir William Alcock, Burgess of Kingston upon Hull and educated at Cambridge. In 1461 he was made dean of Westminster, and his subsequent promotion was rapid in both church and state. In the following year he was made Master of the Rolls,...
's Chantry Chapel - Red Mount Chapel, King's LynnKing's LynnKing's Lynn is a sea port and market town in the ceremonial county of Norfolk in the East of England. It is situated north of London and west of Norwich. The population of the town is 42,800....
- Manchester CathedralManchester CathedralManchester Cathedral is a medieval church on Victoria Street in central Manchester and is the seat of the Bishop of Manchester. The cathedral's official name is The Cathedral and Collegiate Church of St Mary, St Denys and St George in Manchester...
, under the tower - Wells CathedralWells CathedralWells Cathedral is a Church of England cathedral in Wells, Somerset, England. It is the seat of the Bishop of Bath and Wells, who lives at the adjacent Bishop's Palace....
, crossing (by William SmythWilliam Smyth (architect)William Smyth was an English gothic architect responsible for work including the fan vaults at Wells Cathedral, Sherborne Abbey and Milton Abbey. He may also have been the architect of Church of St Bartholomew, Crewkerne.-References:...
) - Church of St Andrew, Mells, porch
- Church of St John the Baptist, AxbridgeChurch of St John the Baptist, AxbridgeThe Church of St John the Baptist in Axbridge, Somerset, England was built in the 13th century and has been designated as a grade I listed building....
, crossing - St Mary's Church, North LeighSt Mary's Church, North LeighThe Parish Church of Saint Mary, North Leigh is the Church of England parish church of North Leigh, a village about northeast of Witney in Oxfordshire.-From Anglo-Saxon foundation until the Reformation:...
, Wilcote chantry chapel - Church of St Peter and St Paul, MuchelneyChurch of St Peter and St Paul, MuchelneyThe Church of St Peter and St Paul in Muchelney, Somerset, England has Saxon origins, however the current building largely dates from the 15th century...
, under the tower - St Bartholomew's Church, Tong, ShropshireTong, ShropshireTong is a village in Shropshire in England. It is near junction 3 of the M54 motorway near Albrighton.The village is remarkable mainly for its church, St Bartholomews, outside of which is the supposed grave of Little Nell, a fictional character in Charles Dickens book, The Old Curiosity Shop...
, chantry chapel - St Mary AldermarySt Mary AldermaryAshlar-faced outside and Gothic throughout, St Mary Aldermary is an Anglican church in Bow Lane in the City of London. The church was badly damaged in the Great Fire of London in 1666, and rebuilt by Sir Christopher Wren.-History:...
, LondonLondonLondon is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
(by Christopher WrenChristopher WrenSir Christopher Wren FRS is one of the most highly acclaimed English architects in history.He used to be accorded responsibility for rebuilding 51 churches in the City of London after the Great Fire in 1666, including his masterpiece, St. Paul's Cathedral, on Ludgate Hill, completed in 1710...
) - Corpus Christi College, CambridgeCorpus Christi College, CambridgeCorpus Christi College is a constituent college of the University of Cambridge. It is notable as the only college founded by Cambridge townspeople: it was established in 1352 by the Guilds of Corpus Christi and the Blessed Virgin Mary...
, main gateway
Gothic revival buildings with fan vaulting
- Wills Memorial BuildingWills Memorial BuildingThe Wills Memorial Building is a Neo Gothic building designed by Sir George Oatley and built as a memorial to Henry Overton Wills III...
, University of BristolUniversity of BristolThe University of Bristol is a public research university located in Bristol, United Kingdom. One of the so-called "red brick" universities, it received its Royal Charter in 1909, although its predecessor institution, University College, Bristol, had been in existence since 1876.The University is... - Middlesex GuildhallMiddlesex GuildhallThe Middlesex Guildhall is the home of the Supreme Court of the United Kingdom and of the Judicial Committee of the Privy Council. It stands on the south-west corner of Parliament Square in London.-History:...
, WestminsterCity of WestminsterThe City of Westminster is a London borough occupying much of the central area of London, England, including most of the West End. It is located to the west of and adjoining the ancient City of London, directly to the east of the Royal Borough of Kensington and Chelsea, and its southern boundary... - Committee staircase, House of LordsHouse of LordsThe House of Lords is the upper house of the Parliament of the United Kingdom. Like the House of Commons, it meets in the Palace of Westminster....
lobbies in the Palace of WestminsterPalace of WestminsterThe Palace of Westminster, also known as the Houses of Parliament or Westminster Palace, is the meeting place of the two houses of the Parliament of the United Kingdom—the House of Lords and the House of Commons... - Saint Patrick's ChurchSt. Patrick's Church (New Orleans)St. Patrick's Church is a Catholic church and parish in the Archdiocese of New Orleans. The parish was founded in 1833, and the current structure was completed in 1840. It is the second oldest parish in New Orleans St. Patrick's Church is a Catholic church and parish in the Archdiocese of New...
, New Orleans, LouisianaNew Orleans, LouisianaNew Orleans is a major United States port and the largest city and metropolitan area in the state of Louisiana. The New Orleans metropolitan area has a population of 1,235,650 as of 2009, the 46th largest in the USA. The New Orleans – Metairie – Bogalusa combined statistical area has a population...
, USA (apsidal fan vault) - Harkness TowerHarkness TowerHarkness Tower is a prominent Collegiate Gothic structure at Yale University in New Haven, Connecticut, United States.The tower was constructed between 1917 and 1921 as part of the Memorial Quadrangle donated to Yale by Anna M. Harkness in honor of her recently deceased son, Charles William...
, Yale UniversityYale UniversityYale University is a private, Ivy League university located in New Haven, Connecticut, United States. Founded in 1701 in the Colony of Connecticut, the university is the third-oldest institution of higher education in the United States...
, New Haven, ConnecticutConnecticutConnecticut is a state in the New England region of the northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, and the state of New York to the west and the south .Connecticut is named for the Connecticut River, the major U.S. river that approximately...
, USA - Centre BlockCentre BlockThe Centre Block is the main building of the Canadian parliamentary complex on Parliament Hill, in Ottawa, Ontario, containing the Commons and Senate chambers, as well as the offices of a number of Members of Parliament and Senators, as well as senior administration for both legislative houses...
, Parliament of CanadaCanadaCanada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, OttawaOttawaOttawa is the capital of Canada, the second largest city in the Province of Ontario, and the fourth largest city in the country. The city is located on the south bank of the Ottawa River in the eastern portion of Southern Ontario... - Strawberry HillStrawberry Hill HouseStrawberry Hill is the Gothic Revival villa of Horace Walpole which he built in the second half of the 18th century in what is now an affluent area of the London Borough of Richmond upon Thames in Twickenham, London...
, London - Balcony in John Rylands LibraryJohn Rylands LibraryThe John Rylands Library is a Victorian Gothic building on Deansgate in Manchester, England. The library, which opened to the public in 1900, was founded by Mrs Enriqueta Augustina Rylands in memory of her late husband, John Rylands...
, ManchesterManchesterManchester is a city and metropolitan borough in Greater Manchester, England. According to the Office for National Statistics, the 2010 mid-year population estimate for Manchester was 498,800. Manchester lies within one of the UK's largest metropolitan areas, the metropolitan county of Greater... - Grand TheatreGrand Theatre LeedsThe Grand Theatre is a theatre and Opera house in the centre of Leeds, West Yorkshire, England. It was designed by James Robinson Watson, chief assistant in the office of Leeds-based architect George Corson, and opened on 18 November 1878...
, LeedsLeedsLeeds is a city and metropolitan borough in West Yorkshire, England. In 2001 Leeds' main urban subdivision had a population of 443,247, while the entire city has a population of 798,800 , making it the 30th-most populous city in the European Union.Leeds is the cultural, financial and commercial... - St John's, EdinburghEdinburghEdinburgh 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...
- Unitarian Church in Charleston, South CarolinaSouth CarolinaSouth Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence...
, USA - Washington National CathedralWashington National CathedralThe Washington National Cathedral, officially named the Cathedral Church of Saint Peter and Saint Paul, is a cathedral of the Episcopal Church located in Washington, D.C., the capital of the United States. Of neogothic design, it is the sixth-largest cathedral in the world, the second-largest in...
, Washington, DC, USA (Children's Chapel) - St Mary's Church, WellingboroughWellingboroughWellingborough is a market town and borough in Northamptonshire, England, situated some from the county town of Northampton. The town is situated on the north side of the River Nene, most of the older town is sited on the flanks of the hills above the river's current flood plain...
- Drawing room, Eastnor CastleEastnor CastleEastnor Castle is a 19th century mock castle, two miles from the town of Ledbury in Herefordshire, England, by the village of Eastnor. It was founded by John Cocks, 1st Earl Somers as his stately home and continues to be inhabited by his descendents. Currently in residence is the family of...
See also
- Barrel vaultBarrel vaultA barrel vault, also known as a tunnel vault or a wagon vault, is an architectural element formed by the extrusion of a single curve along a given distance. The curves are typically circular in shape, lending a semi-cylindrical appearance to the total design...
- Gothic architectureGothic architectureGothic architecture is a style of architecture that flourished during the high and late medieval period. It evolved from Romanesque architecture and was succeeded by Renaissance architecture....