The Palace of Fine Arts is one of those places that makes you stop and stare. A soaring 162-foot rotunda surrounded by classical colonnades, reflected in a tranquil lagoon where swans glide past -- it looks like something transplanted from ancient Rome. It is the sole surviving structure from the 1915 Panama-Pacific International Exposition.
The palace is free to visit and open all hours. Walk the colonnade, sit by the lagoon, and take in the scale of the thing. It is particularly beautiful at dusk when the columns are lit up. The surrounding Marina Green offers views across the Bay to the Golden Gate Bridge.