RM San Martín de Valdeiglesias,

San Martin castle, located in the town centre, was built in the 15th century. It was initially owned by Álvaro de Luna, Duke of Trujillo, the favourite of King John II of Castile, until he wasn’t, and was beheaded in 1453.
Queen Isabel la Católica, was in residence there when she was proclaimed heiress to the Crown of Castilla.
Napoleon’s troops occupied it during the War of Independence and even worse, Hitler’s Condor legion used it as their base during the Spanish Civil war.
Since 2003 the castle has been jointly owned by the Town Hall and José Fernando Cornejo Pablos.
Wine plays an important part in the castle currently, as it is the headquarters of the Denominación de Origen Vinos de Madrid, and wine tastings are regularly held there.