Strong Tower of Santa Cristina Monument · la Bisbal del Penedès, Baix Penedès, Tarragona Fortified house of square plan, today very ruined, located in the municipality of la Bisbal del Penedès (Baix Penedès) and declared a Bien Cultural de Interés Nacional (Catalonia's highest level of heritage protection). It was built in stone, with large blocks in the lower part and rammed earth in formwork above; the façade preserves an arch with large voussoirs and six arrow slits that betray its possible use as a refuge. Next to it stands the Santa Cristina cave. According to the historian Solé i Caralt, it would correspond to a 10th-century castrum, located on the thousand-year-old road from Vilafranca to Valls, at the highest point of the ridge, which served as a refuge for Christians in an area that was a frontier with the Saracens during that century. Photo: Mafricadsp (CC BY-SA 4.0) What to see and do in la Bisbal del Penedès