Mértola’s striking parish church – square, flat-faced and topped with whimsical little conical decorations – is known because in a former incarnation it was a mosque, one of the few in the country to have survived the Reconquista. It was reconsecrated as a church in the 13th century. Look out for an unwhitewashed cavity in the wall, behind the altar; in former times this served as the mosque’s mihrab (prayer niche).
Note also the goats, lions and other figures carved around the peculiar Gothic portal and the typically Moorish horseshoe arch in the north door.
Attached to the church is a small underground museum (head out the rear door of the church and turn right) that has displays of items dating back to the Moorish period found during excavations – including lovely Islamic tiles, 6th-century marble pediments and carved, twisted columns.