Torre del Tostón
La Oliva, Spain
Defense tower “Torre del Tostón” (or "Castillo de El Cotillo") is located in the coastal town of el Cotillo, which forms part of the municipality of la Oliva, Fuerteventura, Spain. This defense tower was recognized as historic-artistic monument in 1949. Nowadays, famous local artists use Torre del Tostón as exhibition room, and it's one of the island's main tourist destinations, including as viewpoint.
Monument data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).