Hall of Transportation, Treasure Island, Historic exhibition hall in Treasure Island, San Francisco, United States

The Hall of Transportation, also called Building 2, is a Moderne-style structure on Treasure Island built in 1938 for the 1939–40 Golden Gate International Exposition. Architects William Peyton Day and George William Kelham designed it as the exposition's transportation hall, with the streamlined lines of the Art Deco era. It was listed on the National Register of Historic Places in 2008.

The building was constructed in 1938 as an exhibition hall for the 1939-1940 Golden Gate International Exposition. Although originally planned as an airplane hangar, it was never used for that purpose and served as an exhibition space instead.

Building 2 took its name from its role as the hall of transportation at the 1939-40 Golden Gate International Exposition, where exhibits on planes, trains and automobiles filled the space. The name survives in the building's identity even though the hangar conversion never happened.

Building 2 stands on Treasure Island, reached from San Francisco via the Bay Bridge and the Treasure Island exit; the island has no direct walking link to the mainland. The building is a Moderne-style structure of 1938, so check locally for current access arrangements before travelling out.

Building 2 was designed by William Peyton Day and George William Kelham, the same pair behind the fair's other halls. Its Moderne styling was meant to read as modern transport, yet the hangar conversion planned for after the fair never happened, leaving the 1938 shell to other uses.