The Battle of City 17 was the first major engagement of The Uprising against the Combine. The oppressed citizens of City 17 took to open combat against the occupying Combine forces after the destruction of Nova Prospekt, a hated and feared symbol of Combine power. Due to the actions of Gordon Freeman and Alyx Vance, the Resistance began openly attacking Combine forces in the city, resulting in a protracted battle which lasted for over a week. The battle ended with the destruction of the Citadel, isolating Combine forces on Earth, the destruction of City 17, and the mutual evacuation of the Resistance and Combine forces from the city.