In September 2024, the San Francisco Board of Supervisors voted 11-0 to designate Gilbert Baker's Rainbow Flag installation at Harvey Milk Plaza as City Landmark No. 319 — placing the flagpole, plinth, and plaque under formal preservation review for the first time.

At the southwest corner of Castro and Market Streets, a 20-by-30-foot flag has flown from a concrete plinth since 1997. In September 2024, the San Francisco Board of Supervisors made that corner official: Gilbert Baker's Rainbow Flag installation at Harvey Milk Plaza is now City Landmark No. 319.

The Board voted 11-0 on September 3, 2024, to pass Ordinance No. 223-24 (File #240725), designating the installation — the flag, its flagpole, concrete plinth, and metal plaque — as a San Francisco landmark. The ordinance was enacted September 13, 2024, and took legal effect October 13.

District 8 Supervisor Rafael Mandelman introduced the process with Resolution No. 170-24 (File #240311), adopted by the Board on April 12, 2024. The Historic Preservation Commission held a public hearing and recommended approval on May 15, 2024. Supervisors Connie Chan, Matt Dorsey, Aaron Peskin, and Catherine Stefani co-sponsored the final ordinance.

"More than a quarter century since the flag was raised over Harvey Milk Plaza, nearly a half-century since Gilbert Baker first conceived the rainbow as a symbol of queer liberation, it's high time for San Francisco to recognize Gilbert Baker's Rainbow Flag installation as the historic landmark it is," Mandelman told the San Francisco Chronicle.

Baker, the San Francisco artist who designed the original rainbow flag in 1978, died in 2017; the landmark designation is made in his name.

The designation changes who decides what happens to the flagpole. Routine maintenance and flag replacement stay with the Castro Merchants Association. But any structural changes to the flagpole, plinth, or plaque now require a Certificate of Appropriateness from the Planning Department's Preservation staff and review by the Historic Preservation Commission. Any effort to disassemble or relocate the installation requires consultation with the Arts Commission.

For anyone walking past the intersection — the flag visible down the slope of Market Street, above the BART station entrance — nothing looks different. The same fabric unfurls from the same pole. What changed is the record at City Hall: under Ordinance No. 223-24, that corner is locked in.