JW Marriott San Francisco Union Square is a luxury hotel located in the heart of San Francisco, offering sophisticated accommodations and exceptional service. It features elegant rooms, modern amenities, and convenient access to iconic city attractions such as Union Square and Chinatown. JW Marriott San Francisco Union Square is a luxury hotel located in the heart of San Francisco, offering sophisticated accommodations and exceptional service. It features elegant rooms, modern amenities, and convenient access to iconic city attractions such as Union Square and Chinatown.