1454 5th Street in Santa Monica was the site of Brother Studios, the recording studio founded by Brian, Dennis, and Carl Wilson of the Beach Boys in the late 1960s. The studio was used extensively for recording through the 1970s and is associated with some of the band's later work. It is now known as Harmony Studios (previously Crimson Sound); the building itself is not a public attraction.
The historical significance is real: the Beach Boys are one of the few bands whose biography is inseparable from a specific California geography, and the studio represents the Santa Monica end of that story. Worth knowing about if you are tracing the city's music history, though the experience of visiting is essentially standing outside a working studio building.