Santa Cruz Beach Boardwalk is California's best oceanfront amusement park, the West Coast equivalent of Coney Island or the parks at the Jersey Shore. Its Giant Dipper roller coaster, a wooden coaster with a lot of style, is one of the oldest in the United States and the park celebrated its 100th birthday in 2007.
Admission is free, so you can wander around and enjoy the atmosphere, then buy tickets only for the things you really want to ride. The Boardwalk is open every day in summer and on weekends and holidays in the off-season, although operations are drastically curtailed in mid-winter and only a few rides may be operating.