I started a group called design east of La Brea, where we organize tours of L.A., peeking into spaces ranging from cutting-edge design projects to all-but-forgotten architectural gems. We visited the Los Angeles Athletic Club, a 100-year-old building in downtown L.A. that’s being slowly renovated to nod to a century of tradition but welcome a new generation of members. On the sixth floor, the glossy wood-paneled walls of the elevator open onto a surprise—a stunning indoor pool. A man was swimming laps, his black swim cap moving slowly along the ornate tile. We all stood there in the humid, chlorine-scented air, in silence, feeling like we’d stepped back in time 50 years. Thousands of people walk by this building every day on busy 7th Street, not knowing that there’s this jewel box of a pool floating somewhere above their heads.