The Prado Museum offers completely free admission during its final two hours every single day: 6-8pm Monday through Saturday, and 5-7pm on Sundays. This isn't a limited promotion—it's permanent museum policy that saves you €15 per person while still guaranteeing access to Velázquez's Las Meninas, Goya's dark paintings, and the entire royal collection.

Strategic approach: Arrive precisely at opening time (6pm weekdays, 5pm Sundays) and head directly to Room 12 on the first floor for Las Meninas—this is the most crowded masterpiece. Counterintuitively, crowds actually thin out after 7pm when locals leave for their evening paseo or dinner preparations, giving you surprisingly peaceful viewing of the Flemish masters in the north wing.

The most convenient metro access is Banco de España station (Line 2, exit toward Calle de Alcalá) or Atocha station (Line 1), both €1.50 from central Madrid. Use the money you save for a proper dinner at nearby Casa Alberto afterward—they've been serving cocido madrileño since 1827.

Important logistics: Security still checks bags thoroughly, and photography is prohibited in most rooms. The museum's free official app provides audio commentary for major works, essential since guided tours aren't available during free hours.