Castillo de San Marcos de El Puerto de Santa María

**Castillo de San Marcos**
	historic site in Cádiz, Spain
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Instance of	castle (Middle Ages);
Part of	Sitio Arqueológico de El Puerto de Santa María;
Location	El Puerto de Santa María, Cádiz Province, Andalusia, Spain
Main building contractor	Alfonso X of Castile and Leon;
Heritage designation	Bien de Interés Cultural (1920–);
	official website
	36° 35′ 47.27″ N, 6° 13′ 36.01″ W
Authority file
	Q97619246; Asset of cultural interest code: RI-51-0000183-00000; Guía Digital del Patrimonio Cultural de Andalucía ID: i19717
	Reasonator; Scholia; Wikidocumentaries; KML file; WikiShootMe; OpenStreetMap; Search depicted;

Castle of San Marcos (also Castillo de Alfonso X El Sabio) is a medieval castle located in El Puerto de Santa María, Andalusia, Spain. The castle was erected as a fortified church by King Alfonso X of Castile. It was built on the site of a mosque of which the wall of the qibla survives.

Alfonso X El Sabio edit