The Museo Nacional del Prado is one of the most famous museums in Madrid and is home to an extensive collection of European art from the 12th to the 19th century. The museum has over 7,000 paintings, including works by Goya, Velázquez, and El Greco. Admission is free from Monday to Saturday from 6 pm to 8 pm and on Sundays and holidays from 5 pm to 7 pm.