San Nicolás de los Servitas
Fodor’s Expert Review
There's some debate over whether the oldest church in Madrid once formed part of an Arab mosque. It was more likely built after the Christian Reconquest of Madrid in 1083, but the brickwork and horseshoe arches are evidence that it was crafted by either Mudejars (Moorish workers) or Spaniards well versed in the style. Inside, exhibits detail the Islamic history of early Madrid.