The Golden Gate Building, built in 1925, is an historic real estate and land development office building located on State Road A1A at 3225 South East Dixie Highway in the unincorporated community of Golden Gate south of Stuart in Martin County, Florida. It was built by the Golden Gate Development Company to serve as the sales office for its 200 block s…The Golden Gate Building, built in 1925, is an historic real estate and land development office building located on State Road A1A at 3225 South East Dixie Highway in the unincorporated community of Golden Gate south of Stuart in Martin County, Florida. It was built by the Golden Gate Development Company to serve as the sales office for its 200 block subdivision called Golden Gate. which was a re-subdivision of a part of the 1911 subdivision called Port Sewall. The Florida Land Boom, however, collapsed before it could be used as such. In 1926, it became the Port Sewall Post Office and it was later used as a church and then as an art studio, before being abandoned and falling into disrepair.