The Euripus Strait is a narrow channel of water separating the Greek

Greece

Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....

 island of Euboea

Euboea

Euboea is the second largest Greek island in area and population, after Crete. The narrow Euripus Strait separates it from Boeotia in mainland Greece. In general outline it is a long and narrow, seahorse-shaped island; it is about long, and varies in breadth from to...

 in the Aegean Sea

Aegean Sea

The Aegean Sea[p] is an elongated embayment of the Mediterranean Sea located between the southern Balkan and Anatolian peninsulas, i.e., between the mainlands of Greece and Turkey. In the north, it is connected to the Marmara Sea and Black Sea by the Dardanelles and Bosporus...

 from Boeotia

Boeotia

Boeotia, also spelled Beotia and Bœotia , is one of the regional units of Greece. It is part of the region of Central Greece. It was also a region of ancient Greece. Its capital is Livadeia, the second largest city being Thebes.-Geography:...

 in mainland Greece. The strait's principal port is Chalcis

Chalcis

Chalcis or Chalkida , the chief town of the island of Euboea in Greece, is situated on the strait of the Evripos at its narrowest point. The name is preserved from antiquity and is derived from the Greek χαλκός , though there is no trace of any mines in the area...

 on Euboea, located at the strait's narrowest point.

The strait is subject to strong tidal currents which reverse direction approximately four times a day. Tidal flows are very weak in the Eastern Mediterranean, and the strait is a remarkable exception. Water flow peaks at about 12 km/hour, either northwards or southwards, and lesser vessels are often incapable of sailing against it. When nearing flow reversal, sailing is even more precarious because of vortex

Vortex

A vortex is a spinning, often turbulent,flow of fluid. Any spiral motion with closed streamlines is vortex flow. The motion of the fluid swirling rapidly around a center is called a vortex...

 formation.

The Swiss scholar Francois-Alphonse Forel

François-Alphonse Forel

François-Alphonse Forel was a Swiss scientist who pioneered the study of lakes, and is thus considered the founder of limnology....

 helped to solve this enigma owing to his study of limnology

Limnology

Limnology , also called freshwater science, is the study of inland waters. It is often regarded as a division of ecology or environmental science. It covers the biological, chemical, physical, geological, and other attributes of all inland waters...

 and the discovery of the seiche

Seiche

A seiche is a standing wave in an enclosed or partially enclosed body of water. Seiches and seiche-related phenomena have been observed on lakes, reservoirs, swimming pools, bays, harbors and seas...

 phenomenon. But the complete solving of the problem is due to the Greek D. Eginitis, director of the Athens Observatory, who published his conclusions in 1929.

Bridges

There are two road bridges across the strait, both at Chalcis. One is a two-pylon, cable-suspended bridge built south of town in 1992, and commonly called the "New" or "High" bridge, with a span of about 215 m (705 ft). The strait is 160 m (525 ft) wide at this point. The bridge is accessible via a fork on the main road at Aulis

Avlida

Avlida or Aulis is a former municipality in Euboea regional unit, Greece. Since the 2011 local government reform it is part of the municipality Chalcis, of which it is a municipal unit. The population was 8,300 inhabitants at the 2001 census, and the land area is 122.235 km². The seat of the...

.

The "Old" or "Low" or "Sliding" Bridge lies across midtown, and can slide away to allow shipping traffic. It is located at the narrowest point of the strait, where it is only 38 m (125 ft) wide. It accommodates two lanes of vehicular traffic. It was originally built as a retractable bridge in 1858, replaced by a rotating one in 1896. The existing, originally wooden bridge was built in 1962 and was extensively refurbished in 1998.

History

The first bridge across Euripus is often said to have been built in 411 BC, i.e. during the Peloponnesian War. In fact, there is no track of this, neither in Thucydides

Thucydides

Thucydides was a Greek historian and author from Alimos. His History of the Peloponnesian War recounts the 5th century BC war between Sparta and Athens to the year 411 BC...

 nor in Xenophon

Xenophon

Xenophon , son of Gryllus, of the deme Erchia of Athens, also known as Xenophon of Athens, was a Greek historian, soldier, mercenary, philosopher and a contemporary and admirer of Socrates...

 who count the story of that conflict (resp. in History of the Peloponnesian War

History of the Peloponnesian War

The History of the Peloponnesian War is an account of the Peloponnesian War in Ancient Greece, fought between the Peloponnesian League and the Delian League . It was written by Thucydides, an Athenian general who served in the war. It is widely considered a classic and regarded as one of the...

and in Hellenica). Probably that date has been proposed because such a bridge was preventing the Athenian fleet to control the strait, control which was a reality until the Athenians' defeat in front of Eretria

Eretria

Erétria was a polis in Ancient Greece, located on the western coast of the island of Euboea, south of Chalcis, facing the coast of Attica across the narrow Euboean Gulf. Eretria was an important Greek polis in the 6th/5th century BC. However, it lost its importance already in antiquity...

 (a few kilometres South of Chalkis) in 411. What is sure is that :

• there was no bridge in 480 (Second Persian War
  Greco-Persian Wars
  The Greco-Persian Wars were a series of conflicts between the Achaemenid Empire of Persia and city-states of the Hellenic world that started in 499 BC and lasted until 449 BC. The collision between the fractious political world of the Greeks and the enormous empire of the Persians began when Cyrus...
  
  ), because many ships passed there at the time of the Artemisio
  Artemisio
  Artemisio is a village and a former municipality in Euboea, Greece. Since the 2011 local government reform it is part of the municipality Istiaia-Aidipsos, of which it is a municipal unit. Population 4,167 ....
  
   battle (see Herodotus
  Herodotus
  Herodotus was an ancient Greek historian who was born in Halicarnassus, Caria and lived in the 5th century BC . He has been called the "Father of History", and was the first historian known to collect his materials systematically, test their accuracy to a certain extent and arrange them in a...
  
  , e.a. VII.173 and VIII.66);
• there was a bridge before 334 B.C. because, as per Strabo
  Strabo
  Strabo, also written Strabon was a Greek historian, geographer and philosopher.-Life:Strabo was born to an affluent family from Amaseia in Pontus , a city which he said was situated the approximate equivalent of 75 km from the Black Sea...
  
  , on the one side Ephorus
  Ephorus
  Ephorus or Ephoros , of Cyme in Aeolia, in Asia Minor, was an ancient Greek historian. Information on his biography is limited; he was the father of Demophilus, who followed in his footsteps as a historian, and to Plutarch's claim that Ephorus declined Alexander the Great's offer to join him on his...
  
   wrote that the strait is so narrow that it was spanned by a bridge only two plethra
  Plethron
  Plethron is a measurement used in Ancient times, equal to 100 Greek feet . It was roughly the width of a typical athletic running-track, and was used as the standard width and length of a Wrestling square, since wrestling competitions were held on the racing track in early times.A plethron is...
  
   long (IX.2.2), and on the other side the people of Chalkis built towers, doors and high walls at the bridge head the year Alexander the Great passed in Asia (X.1.8).

The bridge was apparently rebuilt by the Emperor Justinian I

Justinian I

Justinian I ; , ; 483– 13 or 14 November 565), commonly known as Justinian the Great, was Byzantine Emperor from 527 to 565. During his reign, Justinian sought to revive the Empire's greatness and reconquer the lost western half of the classical Roman Empire.One of the most important figures of...

 in 540 AD. Another was built by the Venetians

Venice

Venice is a city in northern Italy which is renowned for the beauty of its setting, its architecture and its artworks. It is the capital of the Veneto region...

 in the late 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...

; it was called the "Black Bridge" (Italian

Italian language

Italian is a Romance language spoken mainly in Europe: Italy, Switzerland, San Marino, Vatican City, by minorities in Malta, Monaco, Croatia, Slovenia, France, Libya, Eritrea, and Somalia, and by immigrant communities in the Americas and Australia...

: Negroponte

Negroponte

Negroponte can refer to:*the Greek island of Euboea, called Negroponte in Italian**Chalkis, the island's capital, named Negroponte during the Middle Ages...

) and it temporarily gave its name to the town and island.

In his Phaedo

Phaedo

Plato's Phaedo is one of the great dialogues of his middle period, along with the Republic and the Symposium. The Phaedo, which depicts the death of Socrates, is also Plato's seventh and last dialogue to detail the philosopher's final days .In the dialogue, Socrates...

, Plato

Plato

Plato , was a Classical Greek philosopher, mathematician, student of Socrates, writer of philosophical dialogues, and founder of the Academy in Athens, the first institution of higher learning in the Western world. Along with his mentor, Socrates, and his student, Aristotle, Plato helped to lay the...

 has Socrates

Socrates

Socrates was a classical Greek Athenian philosopher. Credited as one of the founders of Western philosophy, he is an enigmatic figure known chiefly through the accounts of later classical writers, especially the writings of his students Plato and Xenophon, and the plays of his contemporary ...

 use the Euripus tide as a simile

Simile

A simile is a figure of speech that directly compares two different things, usually by employing the words "like", "as". Even though both similes and metaphors are forms of comparison, similes indirectly compare the two ideas and allow them to remain distinct in spite of their similarities, whereas...

 for things that "go up and down" in describing the thinking of those who hold that nothing is sound or stable (Phaedo, 90c).

Aulis, the strait's port on the mainland, mentioned by Homer

Homer

In the Western classical tradition Homer , is the author of the Iliad and the Odyssey, and is revered as the greatest ancient Greek epic poet. These epics lie at the beginning of the Western canon of literature, and have had an enormous influence on the history of literature.When he lived is...

 as the launching point of the combined Greek fleets in the Trojan War

Trojan War

In Greek mythology, the Trojan War was waged against the city of Troy by the Achaeans after Paris of Troy took Helen from her husband Menelaus, the king of Sparta. The war is among the most important events in Greek mythology and was narrated in many works of Greek literature, including the Iliad...

, is now a major cement

Cement

In the most general sense of the word, a cement is a binder, a substance that sets and hardens independently, and can bind other materials together. The word "cement" traces to the Romans, who used the term opus caementicium to describe masonry resembling modern concrete that was made from crushed...

shipping terminal.