A small Gothic-Baroque church tucked into the El Carmen quarter, easy to miss from the outside and astonishing on the inside. Built between the 13th and 15th centuries on the site of an earlier mosque, then completely re-frescoed in the 17th century by Antonio Palomino and Dionís Vidal so that the Gothic stone almost vanishes beneath swirling clouds, saints, and trompe-l'œil architecture.
Open daily with a small admission fee that includes an excellent audio guide. Twenty minutes is enough, but it will be a memorable twenty minutes.