Istanbul’s 1,600 Year-Old Harbor Theodosius

Unearthed in Istanbul’s Yenikapı, the Harbor of Theodisius dates back to the 4th century A.D. The excavations undertaken here and onsite in Üsküdar and Sirkeci have produced an archaeological splendor of remains from the Ottoman, Byzantine, Roman, Ancient Greek and Neolithic periods.

Capital of two empires over the centuries, Istanbul has preserved its importance in every period of history. The majestic mosques spread over its seven hills, the districts of Galata and Pera, the Virgin’s Tower and the Golden Horn were a constant source of inspiration to travelers. But the city, which swelled in time to a megalopolis, now faces a transportation problem that began in the 19th century and continues today, a problem the Metro and Marmaray (subway and rail link) projects were created to solve. Initiated by the Department of Transportation, the Marmaray Project will establish a rail link between the European and Asian continents via a tunnel under the Bosphorus.

Before digging for the Metro and Marmaray construction began, archaeological excavations were undertaken by the Istanbul Archaeological Museums in 2004 in the historical texture around the terminals. The cultural treasures brought to light in the excavations, which are being conducted by dig teams with broad participation from diverse areas of expertise, have made a significant contribution to Istanbul’s cultural history.
In particular, the Harbor of Theodosius, one of the most important harbors of the Byzantine period, was brought to light at Yenikapı (‘Vlanga’ in the Ottoman period), a district known for hundreds of years as Istanbul’s fruit and vegetable garden. It is also known from the field notes of travelers who visited Istanbul in the mid-16th century that this harbor, which was built in the 4th century and used up to the 7th century, silted up over time, becoming part of the mainland and used as a truck garden.

The Harbor of Theodosius excavations at Yenikapı
The location of the Harbor of Theodosius was already known from both the written sources and ancient maps. Not known however were the layout, size and exact position of this harbor, which played a key role in the Byzantine economy.

Byzantion was founded at the strategic crossroads between Anatolia and the Balkans and passage from the Aegean and to the Black Sea, a location that contributed enormously to the growth of the city, which came to control the commercial routes thanks to its harbors. Construction of Theodosius Harbor was commissioned by Theodosius I (379-395 A.D.) to meet the needs of the Eastern Roman Empire’s rapidly growing new capital. The harbor was created by building a breakwater that ran from east to west along the south side of a deep natural bay. As well as other structures, a large tower at the far end for guarding the harbor entrance and silos for storing the grain brought by large ships from Alexandria and other ports stood around the harbor. Among them, the Alexandria silo is known from sources to have been the city’s only silo that was still in use in the 10th century when the harbor had largely silted up.

A total of 34 ships were discovered, 13 in the Marmaray excavation and 21 in the Metro excavation, in the archaeological digs undertaken in the harbor area. Falling prey to time, the Harbor of Theodosius silted up with alluvion carried by the Lycos (Bayrampaşa) River, whose waters emptied into the natural bay at the time the harbor was built, leaving it inland about kilometer and half from the Sea of Marmara coast. Farming activity and construction in the city also contributed to the silting process.

Most of the shipwrecks found in the Harbor of Theodosius as a result of the excavations are at the eastern end near the harbor entrance. The harbor is thought to have silted up from the western end to the east and the eastern end to have remained in use until a natural disaster at the end of the 10th or the beginning of the 11th century - perhaps a particularly violent ‘lodos’ (south wind) - largely destroyed the ships anchored here. One of this ships, called YK 1 and thought to have come from Marmara Island laden with amphorae and to have anchored here, is understood from the cargo it was carrying and from the two iron anchors inside it to have been anchored at the harbor when it sank.

The YK 12 is another shipwreck with cargo that has been located in the excavations under way in the harbor area. Besides 16 intact amphorae produced at Ganos (Gaziköy-Tekirdağ), a large number of amphorae fragments were also found on this ship. While it is impossible at present to say with certainty what sort of disaster struck these ships when they sank in the harbor, it is assumed that they were struck by some natural disaster such as a storm or tsunami while others were abandoned because they had outlived their usefulness.

The architectural remains uncovered to the west of the Yenikapı excavation area in the excavations being conducted in the 2nd Zone and in the 3rd Zone to the east of it constitute important data for the history of Istanbul. A quay made of rectangular stone blocks has been identified along a north/south axis at the westernmost edge inside the breakwater. The wooden piles that extend in two parallel rows immediately in front of the stone blocks probably belong to a landing that served as an extension of the quay.

A church building opened up in the northwest sector in the excavations underway in the Metro area was constructed in the 13th century A.D. when the harbor had already begun to silt up. Twenty-three graves have been also brought to light in the excavations under way in and around this church. A second landing, 4.8 meters wide and 11.7 meters long and  built of closely spaced piles, has been identified in the part of the harbor inside the Metro excavation area.  A gold coin from the time of Justinian I (527-565 A.D.) was found in these excavations.

Close to 25,000 artifacts have been discovered so far in the Yenikapı excavations, which are being conducted as part of the Marmaray and Metro Project. The most salient feature of these finds is the information they provide about trade, everyday life, the economy and religious beliefs in the period. Finds such as baked clay tablets inscribed with the names and places of origin of ship owners, stone and iron anchors, capstans and hawsers belonging to the sunken ships and the image of a ship inscribed on an amphora dating to the 10th century are important in terms of providing information about shipping and ship types in the period. Additional finds include close to 2,500 wooden items such as bath clogs, combs and spoons of a dozen different varieties. A scale weight in the shape of a bust of Athena, a bronze balance and weights, lead tablets, bread stamps, a Christ figure, glass bowls with images of Christ, leather sandals, and tools made of bone and ivory reflect everyday life in the period.

Archaeological studies underway in the western and eastern shafts and north and south entrance areas of the Sirkeci Rail Station, as part of the Marmaray project,offer an excellent opportunity for establishing the stratigraphy of a densely built city like Istanbul.  Structural remains from the Early Byzantine, Byzantine and Late Ottoman periods, as well as pottery and small finds from the pre-Roman period have been unearthed.  

Archaeological excavations at Üsküdar Square, another terminal of the Marmaray project, began in 2004 and were completed in 2008. In the Üsküdar Square excavation, remains were found of the foundation of a bazaar the existence of which was known previously from a number of sources. The foundation was reached by drilling in the sub-strata up to a depth of 7 meters, and archaeological material was discovered in the fill dirt. Although no architectural remains from the Roman or earlier periods were encountered in the excavations, a large amount of pottery was recovered together with oil-lamps, stamp seals and coins from the Roman, Late Roman and Byzantine period.