La Moneda Palace is the seat of Chilean government. The President of the Republic and the most important ministries operate there. You can register on the official site and access to guided tours Monday through Friday between 9 am and 5 pm. A must-see is the guard changing ceremony, which takes place every two days, at 10 am on weekdays and 11 on weekends, in Plaza de la Constitution.
METRO STATION: La Moneda, L1.