Conspiracy theorists and rock aficionados fetishize the Masonic – a major concert venue and the Masons' main temple for all California and formerly Hawaii, too. Freemasonry venerates architecture, and this 1958 structure gloriously embodies that philosophy with perfect mid-century-modern style. The marble lobby's focal point is a massive stained-glass window (actually made of crushed colored glass) that depicts Freemasonry's symbols and charmingly simple, sometimes amusing images of early California settlement. The museum focuses on California's Masonic history.

If you're looking for confirmation that California is run by a secret club, here you have it: many of the nation's founding fathers were Freemasons, including George Washington, and the same can be said about California's founders. It's all captured in that modernist crushed-glass window by American artist Emile Norman – if you can decipher the enigmatic symbols and snippets of fabric embedded in the glass. Check out the frieze below the window: it contains separate soil and gravel samples from all 58 California counties, plus Hawaii. Downstairs reveals some of the society's intriguing secrets. Every other Tuesday, the auditorium hosts mass US-citizenship swearing-in ceremonies.