Sometimes the ocean can be a little too vast and a little too cold. If you prefer pools, there are several noteworthy options to choose from.
Plunge. Built in 1925, Belmont Park's 58-yard-long Plunge is the largest heated indoor swimming pool in Southern California. 3115 Ocean Front Walk, Mission Beach, San Diego, CA, 92109. 858/228–9300. www.wavehouseathleticclub.com.