Hartenrod Railway Viaduct (Schlierbach Bridge)

The Hartenrod Viaduct (the so-called Schlierbach Bridge) was built for the Aar-Salzböde Railway (Niederwalgern - Herborn) in 1899-1901 according to plans by the railway construction and operations inspectors Hentzen and Pietig. The structure, made of sandstone and diabase and made of nine arches 150 m long and 13 m high, crosses the valley of the Schlierbach stream in front of its confluence with the salt flats. Similar to the Endbach viaduct, which was built at the same time, there are four arched recesses above each of the pillars.

The viaduct was used for rail traffic for 100 years and is now without any traffic function. It is a listed building.
Source: industriekultur-mittelhessen.de/orte-und-objekte/bad-endbach/hartenrod-eisenbahnviadukt

further information also here:
de.wikipedia.org/wiki/Aar-Salzb%C3%B6de-Bahn

A gigantic structure in Hartenrod, this viaduct. It's a shame that there isn't a cycle path at the top.