Castle of Terena

Portugal, Portugal

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Castle of Terena in Terena, Portugal, was likely begun in the mid-13th century after royal knight Gil Martins and his wife D. Maria João granted the town a charter in 1262, forming part of the strategic frontier defenses along the upper Guadiana River near Castile during King Afonso III's reign.

This pentagonal medieval fortress features granite walls, four semi-circular towers, three angular bastions, a rectangular keep with cruciform arrow slits, and multiple gated entrances including a barbican-protected main gate, with significant remodelings in 1380, 1509 by Duarte d'Armas, and early 16th century under Manuel I by Francisco de Arruda.

Integrated into the Order of Avis's patronage by John I, it endured border conflicts and remains classified as a Property of Public Interest, showcasing Portuguese Gothic military architecture atop a hill overlooking the Alentejo plain.