Joseph Sohm/Visions of America/CorbisThe Century Plaza Hotel by Minoru Yamasaki. Saarinen chairs, “Mad Men,” skinny ties: there’s no doubt that the 1960s are on our minds. But if the Los Angeles Conservancy has its way, its Sixties Turn 50 campaign will do more than inspire retro design. The program’s nine months of tours, discussions and online activities are designed to celebrate and preserve L.A.’s modern architecture, cementing the notion that the sites are, in fact, historic. In the 1960s the city became the epicenter of innovation, thanks not only to the tract houses built after the Case Study Houses program but also to cerebral works like the Los Angeles International Airport Theme Building, the Music Center by Welton Becket in Bunker Hill, the now endangered Century Plaza Hotel by Minoru Yamasaki (above) and the space-pod Chemosphere house by John Lautner. “We just didn’t document our knowledge about the importance of some of these buildings,” says the architectural historian Alan Hess. “We need history to keep ourselves straight.” Scholarship to the rescue. Go to laconservancy.org/sixties.