Castle and Wall of Horta de Sant Joan Monument · Horta de Sant Joan, Terra Alta, Tarragona Image of Horta de Sant Joan, not of the place itself. The castle and wall of Horta de Sant Joan form a set of defensive structures of the town, in the Terra Alta, declared Bien Cultural de Interés Nacional (Catalonia's highest level of heritage protection). The founding of Horta is unknown, though it seems to owe its origins to the Arabs of Tortosa; the first mention of the castle dates from 1153, cited in the donation of the castle of Miravet to the Temple. In 1165 King Alfonso the Chaste granted the first charter of settlement for the Terra Alta, reserving the castle for himself; in 1166 it was in the hands of the Montcada family and passed to the Templars in 1182, becoming the seat of their commandery of Horta from 1193. The keep, the last standing element, was demolished in 1771. The commandery passed to the Hospitallers in 1317, who kept it until the 19th century. Photo: Hans Hillewaert (CC BY-SA 3.0) What to see and do in Horta de Sant Joan