Castillo de Santa Olalla del Cala is a fortress located in Huelva province, commissioned by King Sancho IV el Bravo in 1293 as part of the Banda Gallega defensive system. The castle features an irregular floor plan with a north-south orientation, encompassing 4,610 square metres of walled surface with 10 wall sections and 10 towers, reflecting Gothic Christian medieval design with Mudéjar influences. Reinforced in 1386–87 and again in 1466–67 due to territorial conflicts and political instability, the fortress exemplifies late medieval Castilian military architecture. The castle underwent restoration by Andalusia's Ministry of Culture in 2006 and is protected as a Cultural Interest Asset.
