Bridge near Kemer

The visible remains still allow the identification of some, for their time, unusual construction techniques. The extant ramp features three arches of 4 to 4.45 m clear span, two of which, with an apex height of only 1 m, show a particularly flat profile.[3] Segmental arches are known only from a limited number of Roman bridges, and came into widespread use not until the late medieval period (see e.g. Ponte Vecchio). The third arch, in contrast, possesses the typically Roman semi-circular shape, with a span-to-rise ratio of 2 to 1.[3]

The arch vaults were constructed from locally hewn limestone ashlar which was bound by mortar; the interior of the bridge body was built of a rock-hard mixture of rubble and fluid mortar, which today lays bare at many places, shining through the crumbled facing.[3] The mortar consists of hard building lime with an admixture of fine gravel.[3] The pavement of the roadway has completely disappeared, but the constant gradient of the ramp indicates that the ancient paving stones lay directly on the present-day surface.[3]

Third arch of the Seydikemer Bridge. Above the arch vault is the hollow chamber. The circular ducts supported the Roman scaffolding and falsework during construction. At the bottom left a small, arched floodway is visible.

Another remarkable feature of the Seydikemer Bridge is the hollow chamber above the third arch vault, where the 2 m large gap between the arch crest and the roadway is not filled with the mortar mixture, but features in its interior a cut-out chamber measuring 3.5 m in length, 3.2 m in width and 1.5 m in height;[4] its purpose was to reduce the load resting on the arches, and to save building material.[3] A second, smaller inner chamber was found in the upper part of the second pier.[5] Similar hollow chamber systems are known from at least three other Roman bridges in Asia Minor, such as the Makestos Bridge, the Aesepus Bridge and the White Bridge.[6]

Circular ducts with a diameter of approximately 26 cm, which run through the length and width of the bridge, are interpreted as hollow forms of round construction timber of the Roman scaffolding and falsework.[7] In the third pier, which stands closest to the river bed, a small, arched floodway is integrated to let water pass.[7] Although the surviving ramp does not allow to determine the number and type of the arches of the bridge proper, the ancient structure must have been a rather impressive engineering feat, judging from its current height of 8 m above the sediments and the 500 m wide river bed which needed to be spanned.[7]

A well-preserved example of an ancient segmental arch bridge in Lycia is the twenty-eight arch Limyra Bridge, which was also investigated by the German archaeologists Wolfgang W. Wurster und Joachim Ganzert.

A possible starting point for the dating of the Seydikemer bridge provides a Roman road in the area which is known to have existed at the beginning of the 3rd century AD.[7] According to this interpretation, the bridge may have been part of a westward route from Kadyanda (Üzümlü), which descended further upstream into the Xanthos valley.[8] Possibly, the bridge can be also linked with the pass trail to Oinoanda.[8]

• 
  View from the western ramp
• 
  Remains seen from river
• 
  View from west
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  Hollow chamber below roadway
• 
  Second segmental arch

• List of Roman bridges
• Roman architecture
• Roman engineering

• O’Connor, Colin (1993), Roman Bridges, Cambridge University Press, p. 126 (E22), ISBN 0-521-39326-4
• Wurster, Wolfgang W.; Ganzert, Joachim (1978), "Eine Brücke bei Limyra in Lykien. Anhang: Reste einer Brücke oberhalb von Kemer am Oberlauf des Xanthos", Archäologischer Anzeiger (in German), Berlin: German Archaeological Institute, pp. 304–307, ISSN 0003-8105

Media related to Kemer Seydikemer at Wikimedia Commons