The Palace of Fine and Decorative Arts, also known as Building 3, on Treasure Island in San Francisco Bay, California, was an aircraft hangar constructed in 1938 for Pan American World Airways' trans-Pacific Clipper services, and then modified for the 1939-40 Golden Gate International Exposition.

Building 3 was one of a pair of identical hangars built to house Pan American's flying boats at the south end of the island.

At the end of the exposition all structures but Buildings 1, 2 and 3 were to be torn down to make way for the development of the reclaimed land as an airport for San Francisco.

A formal entrance faces northwest in a concave indentation with scallops or broad flutes in the surface of the marquee over the door.

[2] The interior was fitted out for the exposition with curving temporary plaster walls to house a $20 million collection of artwork, designed by Dorothy Wright Liebes and Shepard Vogelsang.

The station trained security forces for merchant ships after the United States' entry into World War II.