In what city in the dystopia alternate future of Half-Life 2 do you first start in?

In the dystopia alternate future of the game Half-Life 2, you first start in the City 17. The reason for this is that City 17 serves as the primary setting for the game, set in a world where a totalitarian alien race known as the Combine has taken control. The city is depicted as a grim and oppressive environment, tightly controlled by the Combine forces. As the protagonist, Gordon Freeman, you begin your journey in City 17, getting involved in the resistance movement against the Combine and embarking on a quest to liberate humanity from their rule.