Jerez' muscular yet elegant 11th- or 12th-century fortress is one of Andalucía's best-preserved Almohad-era relics. It's notable for its octagonal tower, typical of Almohad defensive forts, reached through Islamic-style gardens, past a 12th-century mosque-turned-chapel, the sprawling Patio de Armas and the 17th- and 18th-century baroque Palacio Villavicencio.
On the left as you enter is the beautiful mezquita (mosque), transformed into a chapel by Alfonso X in 1264, though retaining its fountain and horseshoe arches; it's the only remaining one of 18 mosques that once stood in Jerez. On the right, the Palacio Villavicencio, built over the Almohad palace ruins, is known for its bird’s-eye views of Jerez; the camera obscura inside its tower provides a picturesque panorama of the city.
Beyond the Patio de Armas, the peaceful gardens recreate the ambience of Moorish times with geometric flower beds, tinkling fountains, and the well-preserved, domed Almohad Baños Árabes (Arabic Baths), with their star-shaped shafts of light.