Several very important battles between Spanish royalist forces and the pro-Independence troops under Bolivar took place in the Carabobo region. The most important was the Battle of Carabobo, fought on 24 June 1821 and considered a key battle in the struggle for Venezuelan independence. After the battle, what was left of the Spanish forces holed up in the San Felipe Castle in Puerto Cabello until 10 November 1823, when they surrendered and left Venezuela.