Justinian Sangarius Bridge or Bridge (popularly: Beşköprü), in Turkey, dating from the late Roman period, is a stone bridge over the River Sakarya. The building was built by the Eastern Roman Emperor Justinianus (527-565) to facilitate transportation between the capital Constantinople and the empire's eastern provinces. The bridge, which is almost 430 meters long, was the subject of the works of writers and poets of the period due to its huge dimensions. The claim that Justinian was planning a canal project to cross Anatolia by ship instead of the Bosphorus and that the bridge is a part of this project is discussed by experts. The bridge was added to the World Heritage Tentative List by UNESCO in 2018.
Location and history
Justinianus Bridge is located in the northwest of Anatolia, 5 kilometers from Adapazarı, in the historical Bitinya region. According to the late Roman historian Prokopius, it was built instead of a mobile bridge consisting of boats connected to each other. Transportation on the Sakarya River was interrupted every time the boats broke off frequently due to the strong current and disappeared with the current. The fact that Emperor Justinian built a stone bridge was also predicted to be related to the great strategic importance of the river crossing, as an ancient kingdom road ran from Constantinople to the border of the Sassanid Empire, where Justinian often fought.
The construction time of the Justinian bridge could be determined precisely by using different literary sources. According to them, construction of the bridge began in the autumn of 559, when Justinian was returning from a study journey to Thrace, and was completed after the peace treaty with the Sassanid Empire in 562. According to the historian Theofanis, the construction of the bridge began in Annus Mundi in 6052, which corresponds to the year 559 or 560. It can be understood from the poems of Paulus Silentiarius and Agathias that the building was completed in 562, praising Emperor Justinian and his works. Bridge building, on the other hand, provided a clue for dating ancient literary works: Prokop stated in his important work on late Roman architecture, De Aedificiis, that the bridge is still under construction, so it can be assumed that he published this work in 560-561 years - usually five or six years than is believed. Since the old bed of the broad Sakarya River shifted to the east for about 3 kilometers, today the structure is on the small Çark Creek (ancient name: Melas), which is an outlet of Sapanca Lake (ancient name: Sophon).
Justininanos bridge is made entirely of limestone. The well-preserved building has a length of 429 m with its abutments at both ends, and its magnificent dimensions with a width of 9,85 m and a height of about 10 m. The splendor of the building is emphasized by arches, each 23 to 24,5 m wide. Bridge piers are approximately 6 m wide. Five arches in the middle of the river terminate with two arches, one 19,5 m wide and the other 20 m wide; Çark Creek flows under one of its arches on the west side. In addition to the river bed, in the flood zone, there are also five archways of 3 to 9 meters wide to protect the bridge from flooding. Two of them are on the west coast and three are on the east coast. Those on the east coast were partially destroyed during the construction of a single track railway. The thickness of each of the two bridge piers at the transition from the coastal zone to the seven arches on the riverbed is approximately 9,5 m. The end stones of the seven great arches used to have crosses, possibly symbols of Christianity, but only two of these have survived to this day.
All of the river legs have been given the feature of breakwaters with pointed facades in the direction of the flow and rounded facades in the direction of the flow. The only exception is the foot on the west coast, which is the widest with a width of 9 m. The facades of this pillar in both directions are sharp. With these features, this bridge is distinctly distinguished from other Roman period bridges known in terms of architecture, as most of them have sharp breakwaters in both directions.
At the western end was a triumphal arch that was common on Roman bridges until the 19th century but has disappeared today. On the eastern end, there is an apse that has survived today but whose function is unknown. This round structure facing east is thought to be a religious altar. The height of the apse is 11 m, and its width is 9 m. The triumphal arch and apse were drawn by Léon de Laborde in 1838. Laborde's drawing shows a round arched door made entirely of cut stone, opening directly to the bridge. Another sketch gives information about the dimensions of this door: Accordingly, the door was 10,37 m high and 6,19 m wide; column thickness was 4,35 m; One of the pillars was a winding staircase.
The bridge was decorated with an inscription from Agathias containing a Greek wit. The inscription has not survived, but its content has been preserved in the writings of Emperor Konstantinos Porphyrogenetos:
- Καὶ σὺ μεθ 'Ἑσπερίην ὑψαύχενα καὶ μετὰ Μήδων ἔθνεα καὶ πᾶσαν βαρβαρικὴν ἀγέλην, Σαγγάριε, κρατερῇσι ῥοὰς ἁψῖσι πεδηθεὶς οὕτως ἐδουλώθης κοιρανικῇ παλάμῃ · ὁ πρὶν γὰρ σκαφέεσσιν ἀνέμβατος, ὁ πρὶν ἀτειρὴς κεῖσαι λαϊνέῃ σφιγκτὸς ἀλυκτοπέδῃ.
- Now, O Sangarios, whose flood waters pass between these pillars; You too now flow with the hand of a ruler as his servant wants, just like the proud Hespera and Med peoples and all the Barbarian masses. You, who once stood up to ships, once restless, are now among the shackles hit by impenetrable stones.
Ancient canal project
The construction of the Justinian bridge is today considered by some experts as a sign of the existence of a large canal project, which was assumed to have been planned during the time of Emperor Justinian, which could not be realized as a result. Accordingly, the aim of this project was to connect the Sea of Marmara to the Black Sea by channels passing through Anatolia, without using the Bosphorus. The earliest records of the planned canal construction were found in the correspondence between Emperor Trajan and the governor of Bithynia Pliny. In these correspondence, Plinius suggested excavating a link from Sapanca Lake near the Sakarya river to Propontis. The project in question is thought to have never been realized, especially since Plinius died soon after.
According to Moore, Justinian planned to direct the part of the Sakarya River flowing into the Black Sea to Sapanca Lake in the west direction and in this way he thought of realizing the project of Pliny. According to Moore, the enormous dimensions of the river flowing under the Justinian bridge and the pointed sides of the piers facing the current today, unlike other Roman bridges, are signs that strengthen this thesis. Whitby does not accept this thesis, arguing that the Sakarya River is not suitable for the passage of ships on the riverbed and that the pointed bridge piers facing the current are also found in other bridges. Froriep, on the other hand, emphasizes the possibility of such a project, arguing that it is possible to change the flow direction according to local topographic features.