Rifleman's Fort of Ferriols Monument · Corbera d'Ebre, Terra Alta, Tarragona Rectangular-plan fort with chamfered corners and several rows of arrow slits symmetrically arranged on all its faces, built in the municipality of Corbera d'Ebre during the 19th-century Carlist wars as part of a defensive line with a perimeter moat about a hundred metres long. Built of rubble masonry, with walls 60 centimetres thick, it had three low-height levels and an interior of barely 4.5 by 5.4 metres. It is declared Bien Cultural de Interés Nacional (Spain's highest level of heritage protection) and is reached across open fields. Photo: 11299883 (CC BY-SA 2.0) What to see and do in Corbera d'Ebre