Polished storefronts around you conceal more layers of history than San Francisco's luxury retail and hotel district first suggests. Union Square got its name from the pro-Union rallies held here before and during the Civil War, when San Francisco — a city with significant Southern sympathies — was politically contested territory. The 97-foot Dewey Monument at the center of the square commemorates Admiral George Dewey's victory over the Spanish fleet at Manila Bay in 1898, the battle that launched the United States as a Pacific power.
The park sits above a four-level underground parking garage built in 1942, the first underground parking structure in the United States. The square is surrounded by the flagship stores of nearly every major luxury brand, a retail density comparable to Fifth Avenue in New York or the Champs-Élysées in Paris. The St. Francis Hotel on the west side of the square, opened in 1904, survived the 1906 earthquake but burned in the subsequent fire; the current building opened in 1907.
The hotel's coin-washing machine — which cleaned the coins handled by guests to prevent soiled gloves — was famous enough that clean, shiny coins became known as St. Francis Mint coins. Dashiell Hammett set Sam Spade's office near here; the Maltese Falcon is a Union Square novel.