The Mission District is located in east-central San Francisco. Its border to the east is U.S. Route 101, which forms the boundary between the eastern portion of the district, known as "Inner Mission", and its eastern neighbor, Potrero Hill. Sanchez Street separates the neighborhood from Eureka Valley (also known as "the Castro") and Noe Valley to the west. The part of the neighborhood from Valencia Street to Sanchez Street, north of 20th Street, is known as the "Mission Dolores" neighborhood. South of 20th Street towards 22nd Street, and between Valencia and Dolores Streets is a distinct neighborhood known as Liberty Hill. Cesar Chavez Street (formerly Army Street) is the southern border; across Cesar Chavez Street is the Bernal Heights neighborhood. North of the Mission District is the South of Market neighborhood, bordered roughly by Duboce Avenue and the elevated highway of the Central Freeway which runs above 13th Street.
The principal thoroughfare of the Mission District is Mission Street. South of the Mission District, along Mission Street, are the Excelsior and Crocker-Amazon neighborhoods, sometimes referred to as the "Outer Mission" (not to be confused with the actual Outer Mission neighborhood). The Mission District is part of San Francisco's supervisorial districts 6, 9 and 10.
The Mission is often warmer and sunnier than other parts of San Francisco. The microclimates of San Francisco create a system by which each neighborhood can have radically different weather at any given time, although this phenomenon tends to be less pronounced during the winter months. The Mission's geographical location insulates it from the fog and wind from the west. This climatic phenomenon becomes apparent to visitors who walk downhill from 24th Street in the west from Noe Valley (where clouds from Twin Peaks in the west tend to accumulate on foggy days) towards Mission Street in the east, partly because Noe Valley is on higher ground whereas the Inner Mission is at a lower elevation.