Fort on the Serra dels Valencians Monument · Riba-roja d'Ebre, Ribera d'Ebre, Tarragona Image of Riba-roja d'Ebre, not of the place itself. A 19th-20th century fortification of which remains survive of a quadrangular tower with corners cut on the bias, situated on a hill of the serra dels Valencians, south of the hydroelectric power station, in the municipality of Riba-roja d'Ebre. It retains a few loopholes, and its walls are made of stones of various sizes bonded with mortar and laid in irregular courses. Photo: Profrob (CC BY-SA 4.0) What to see and do in Riba-roja d'Ebre