 The Bridge near Limyra ( in Turkish : Kırkgöz Kemeri , " Bridge of the Forty Arches " ) is a late Roman bridge in Lycia , in modern south @-@ west Turkey , and one of the oldest segmented arch bridges in the world . Located near the ancient city of Limyra , it is the largest civil engineering structure of antiquity in the region , spanning the Alakır Çayı river over a length of 360 m ( 1 @,@ 181 @.@ 1 ft ) on 26 segmental arches . These arches , with a span @-@ to @-@ rise ratio of 5 @.@ 3 : 1 , give the bridge an unusually flat profile , and were unsurpassed as an architectural achievement until the late Middle Ages . Today , the structure is largely buried by river sediments and surrounded by greenhouses . Despite its unique features , the bridge remains relatively unknown , and only in the 1970s did researchers from the Istanbul branch of the German Archaeological Institute carry out field examinations on the site . 
