Sangarius Bridge
Coordinates: 40 ° 44 ′ 15 ″ N , 30 ° 22 ′ 22 ″ E
| Sangarius Bridge (Justinians Bridge ) |
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| Convicted | Strait of Constantinople heading east in Byzantine times | |
| Crossing of | Çark Deresi (ancient: Sakarya ) | |
| place | Near Adapazarı ( Turkey ) | |
| construction | Arch bridge with vaulted vaults | |
| overall length | 429 m | |
| width | 9.85 m | |
| Number of openings | 12 | |
| Clear width | Max. 24.5 m | |
| Pillar strength | Max. 9.5 m | |
| height | 10 m | |
| construction time | 559-562 | |
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The Sangarius Bridge or Justinians Bridge ( Turkish : Justinianos Köprüsü or Beşköprü ) is a late Roman stone bridge over the Sangarius River (modern: Sakarya ) in what is now Turkey . The building was built by the Eastern Roman Emperor Justinian (527-565) to improve communication between the capital Constantinople and the eastern provinces of his empire. The considerable dimensions of the almost 430 m long bridge found their literary expression in several works by contemporary authors and poets. The attribution of the bridge to a canal construction project allegedly planned by Justinian for the extensive circumnavigation of the Bosporus through the Anatolian hinterland is controversial among experts.
Location and history
The Sangarius Bridge is located in northwestern Anatolia , in the ancient Bithynian countryside , five kilometers from the city of Adapazarı in the Serdivan district . According to the testimony of the late antique historian Prokop in his work De Aedificiis , it replaced a pontoon bridge made of lashed barges, which was repeatedly torn away by the strong currents, making the Sangarius often impassable. The construction of a permanent bridge on the orders of Emperor Justinian is likely to be related to the particular strategic importance of the river crossing, as one of the ancient military roads from Constantinople to the Persian border ran here, where under Justinian there were repeated violent armed conflicts with the Sassanid Empire .
The construction time of the Sangarius Bridge can be determined quite precisely from various literary sources. It began at the latest in the autumn of 559, when Justinian returned from a tour of inspection from Thrace , and ended in 562 after the peace agreement with Persia. The later chronicler Theophanes lists the start of construction under annus mundi 6052, which corresponds to the year 559/60 AD. Two poems by Paulos Silentiarios and Agathias speak for the completion of the building in 562 , which were written in eulogies for Emperor Justinian and his deeds. Conversely, the bridge works may also offer a clue to the dating of ancient literature: Since Prokop describes the bridge as being under construction in his important work on late Roman architecture, the aforementioned De Aedificiis , his work, the dating of which has long been controversial, seems, according to Michael Whitby to have been written around 560-561, five to six years later than generally accepted. Researchers who hold on to the early dating of the De Aedificiis , however, doubt the dating of Theophanes, which is why Whitby's position has not generally prevailed. It seems certain that bridge 562 was completed, but construction work can also start a little earlier.
Nowadays the building only spans the insignificant Çark Deresi (ancient: Melas), an outflow from the nearby Lake Sapanca (ancient: Sophon), while the much larger Sakarya has moved its bed three kilometers to the east.
construction
The entire Sangarius Bridge is made of limestone . The well-preserved structure, including both abutments, has a considerable length of 429 m, a width of 9.85 m and a height of approx. 10 m. The impressive overall size is underlined by five main arches, the clear width of which is 23 to 24.5 m. The width of the associated bridge piers is around 6 m. The arch quintet in the middle of the river is framed by two smaller bridge arches with 19.5 m and 20 m clear width; The Çark Deresi stream flows through one of the western arches. Outside the river area, in the flood zone, the bridge is broken through by five arched openings between 3 and 9 m span, two of them on the western and three on the eastern bank of the river. The latter were partially or completely destroyed by the construction of a single-track railway line along the river. The thickness of the two bridge piers at the transition from the bank zone to the seven arches in the river bed is around 9.5 m each. The keystones of the seven largest arches were probably adorned with small Christian crosses, but all but two of them were destroyed.
In detail, the clear arch widths from west to east are in m (pillar thicknesses in brackets):
- 3 (nb) 7 (9.5) 19.5 (6) 23 (6) 24.5 (6) 24.5 (6) 24 (6) 24.5 (6) 20 (9.5) 9 ( nb) 6 (nb) 3
The river piers are continuously provided with breakwaters , which have a rounded shape on the stream side and an acute-angled shape down the river. An exception is the pillar, the widest 9.5 m, on the western staircase, the breakwater of which is wedge-shaped on both sides. The construction thus deviates significantly from the majority of Roman bridges, in which the breakwaters point away from the bridge at an acute angle both upstream and - if available - downstream.
Up until the 19th century, a triumphal arch that has since disappeared from the western driveway towered up until the 19th century - as is not unusual with Roman bridges - while a conche has been preserved on the eastern side to the present day , but its function is unclear. Possibly the east-facing semi-dome building is a religious shrine. Its height is 11 m, the width 9 m. The triumphal arch and conche were recorded in a drawing by Léon de Laborde in 1838 . It shows a round arched gate constructed exclusively from stone blocks directly at the entrance to the bridge. Another sketch provides some dimensions of this arch: According to this, the gate opening was 10.37 m high and 6.19 m; wide, while the pillars were 4.35 m thick; A spiral staircase ran up one of the two pillars.
The inscription on the bridge, which has no longer survived, bore an epigram by the poet Agathias, quoted by Emperor Konstantin Porphyrogenetus (905-959):
- You, too, Sangarios, whose impetuous course is broken through these arches, are now flowing there, slave of an act of rulership, like the proud Hesperia and the Median peoples and all barbaric hordes. Once a rebel against the ships, once untamed, you now lie in the fetters of indomitable rock.
Ancient sewer projects
The construction of the Sangarius Bridge is seen by some experts as an indication of a - ultimately not materialized - large canal project under Justinian, which aimed to circumnavigate the Bosporus through the Anatolian inland. The first reports about a planned canal construction can be found in the correspondence between Emperor Trajan and the Roman governor of Bithynia Pliny , who suggested a breakthrough from Lake Sapanca, which is located near Sangarios, to Propontis . However, not least because of the imminent death of Pliny, the plan never seems to have been realized.
According to Moore, Justinian intended to divert the course of the Sangarius to the Black Sea westward into the Sapanca Sea in order to implement Pliny’s plan in this way. Evidence for this is on the one hand the grotesque disproportion between the enormous dimensions of the bridge and the modest Melas, and on the other hand the fact that the pointed bridge piers - contrary to Roman custom - nowadays point downstream. Whitby, on the other hand, rejects the hypothesis, pointing out that the Sangarios was not navigable in the course in question and that wedge-shaped breakwaters can also be found on the underwater side of other Roman bridges. Froriep takes a middle position, showing that a reversal of the direction of flow could have been implemented in view of the very low gradient of the local topography .
See also
- List of Roman bridges
- Roman architecture
- Roman construction technology
- List of antique spiral stairs
Remarks
- ^ What Laborde overlooked in his 1838 bridge sketch shown above (Whitby 130).
Individual evidence
- ↑ a b c d e f Whitby (1985), p. 129.
- ^ Prokop, De Aedificiis , 5.3.8-11
- ^ Whitby (1985), p. 141.
- ^ All information: Whitby (1985), pp. 136-141.
- ↑ Whitby (1985), pp. 141-147.
- ↑ a b c d Froriep (1986), p. 46.
- ↑ Whitby (1985), pp. 129f.
- ↑ Froriep (1986), p. 46f.
- ↑ a b c Whitby (1985), p. 130.
- ↑ Whitby (1985), p. 130 (Fig. 2)
- ↑ a b Froriep (1986), p. 47.
- ↑ Laborde (1838), plate 14, no.30
- ↑ Laborde (1838), plate 14, no.31
- ↑ Pliny 10.41-42, 61-62
- ^ Moore (1950), p. 109.
- ↑ Whitby (1985), pp. 130-133, 136.
- ↑ Froriep (1986), pp. 47-50.
literature
- Siegfried Froriep: A waterway in Bithynia. Efforts by the Romans, Byzantines and Ottomans. In: Ancient World . 2. Special number, 1986, pp. 39-50.
- Léon de Laborde: Voyage de l'Asie Mineure. Didot, Paris 1838, pp. 32-34 (and Plate XIV, No. 30 & 31).
- Frank Gardner Moore: Three Canal Projects, Roman and Byzantine. In: American Journal of Archeology . Vol. 54, No. 2, 1950, pp. 97-111.
- Michael Whitby : Justinian's Bridge over the Sangarius and the Date of Procopius' de Aedificiis. In: The Journal of Hellenic Studies . Volume 105, 1985, pp. 129-148.
