And now, it is launching a year-long celebration to mark its 100th anniversary.
"This is the building under construction. In around 1923, you can see the sand dunes," said Isabella Lores-Chavez, Ph.D., associate curator of European paintings, while pointing to a black and white photograph. She says the early story of the Legion of Honor is intertwined with a unique San Francisco character who helped build it: Alma Spreckels.
"Alma de Bretteville Spreckels is a San Francisco-born lady who became the kind of grand dame of San Francisco. She was born in the outer, outer lands right in the outer sunset and grew up in a farmhouse," Lores-Chavez said. "And allegedly, she was the model for the figure at the top of the pillar in Union Square. It's a figure of victory. So she, you know, had sort of made a name for herself that way as a great beauty."
She was a beauty who caught the eye of millionaire sugar magnet, Adolph Spreckels. Their marriage in 1908 gave her money, status and eventually a plan to create a stunning museum.
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"It was a huge deal. The mayor was here the day of the opening, and he said that during the opening ceremony, he said that this this would be a palace that would endure for many generations. And, of course, that has come true, you know, with our celebration of 100 years," Lores-Chavez said.
By the mid 1920s, the socialite--dubbed "Big Alma" because of her height--was amassing an even bigger art collection that would help fill the museum she and Adolph Spreckels would donate to San Francisco. Most famously, was an original cast of "The Thinker" by sculptor Auguste Rodin.
"And then those became some of the founding Rodin's in our collection, including "The Thinker," which sets out in the court of honor and has been there since 1924 since the day we opened," Lores-Chavez said.
San Franciscans young and old have stopped to snap a selfie.
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And the magic continues over the generations.
Lores-Chavez says the centennial exhibitions and year-long celebration will include everything from classical pieces, like a canape belonging to Marie Antionette, to contemporary artists and performers.
"So, it's really an opportunity to invite the full diversity of the Bay Area to participate in this, the wonders that we have at this museum," she said.
The exhibitions will also include some new twists, including introductory text in languages that include Spanish and Mandarin, along with a free audio guide.
It is a celebration of art, a Bay Area landmark, and the woman who did so much to create it.