The Palace of Fine Arts in San Francisco

Panorama of the original Palace circa 1919. All pics sourced from the Wikipedia article. 

One of the most iconic landmark buildings in San Francisco other than the Golden Gate Bridge may just be the Palace of Fine Arts. Constructed specifically for the 1915 Panama Pacific International Exposition (another rabbit hole unto itself), the building was constructed specifically to look like a decaying ancient Roman ruin. The architect, Bernard Maybeck, viewed it as making a fictional ruin from another time.  

The original complex of buildings built for the expo. 

The complex of buildings created for the Exposition, most of which were demolished afterward, which is nothing short of just criminal. Thankfully, the Hearst family (yes, THAT Hearst family) started a "Palace Preservation League" to keep the palace preserved from demolition.  

After being preserved, it had a rather varied history of things being located there. The 30s saw it being the home of many lighted tennis courts, then the WW2 years saw it become a military motor pool, the post war years saw it become a UN limousine motor pool, then became a city park department warehouse, and a temporary fire department headquarters. 

After all this kind of usage, the palace was falling apart, as it was made of substandard materiel as it was only expected to stand for the duration of the Expo. So, in 1964 the entire facility was demolished, only leaving some of the original steel frames. Then, the effort to reconstruct it was started with more durable materials to ensure a more permanent structure, which was completed in 1974. In reconstructing it, there was painstaking effort to recreate it exactly as it was in both shape, size and color, the only difference other than building material, was the lack of some of the original murals that adorned the original structure. 

The palace is also a popular filming location, with scenes filmed in it for movies and shows such as Vertigo (1958), Time After Time (1979), So I Married An Axe Murderer (1993), The Rock (1996), Mission impossible (tv series), and Game of Thrones. It was also included by the developers into the game SimCity 4. Another show business connection it has is the Lucasfilm headquarters were located very close by at the Letterman Digital Arts Center just behind the Palace, and a plaque for the foundation is embedded in the Palace floor underneath the dome. It was also likely the inspiration for the architecture for Naboo in Star Wars Episode 1. 

Of course, in 1964 the Exploratorium was hosted there for a majority of the new structure's lifetime until 2013. In 2010, there were renewed efforts to start new restoration works and ensure the structure was seismically sound. Today, it operates as a facility available for rent for trade events or weddings.