Segura Bridge

Segura Bridge is a Roman bridge connecting Segura, in Idanha-a-Nova, Portugal, to the Spanish municipality of Alcántara [1]. The bridge was built over the Erges river, a tributary of the Tagus [1]. It has five arches; only two of the original Roman arches, the ones closer to both river banks, survive to this day, with the rest being added during reconstructions in the 16th and 19th centuries [1]. The stonemason work done during the 1571 reconstruction of two of the arches is considered to be "barely distinguishable" from the original [1]. The bridge was constructed over the gorge created by the Erjas river in the local slate [1]. It comprises five arches with barrel vaults; the central arch spans 10.5 m [1]. Its structure is made of ashlar masonry with cushioned pink granite blocks, measuring 2.85 to 3 m in section [1].