Sand Dune Park is a surprisingly large natural sand dune in the middle of a residential neighborhood, used by the locals primarily as a fitness challenge. The main face of the dune rises about 100 feet and serves as a de facto outdoor gym — people sprint up and plod back down, over and over, in the California tradition of turning natural features into workout equipment.
For the non-fitness-obsessed, it is a curious geological remnant in an otherwise fully developed suburban landscape. Access to the dune face is managed to prevent overuse — timed entry slots are required on busy days — but the surrounding park area is open freely. It is a five-minute detour from the beach, worth it for the oddity of running into a genuine sand dune between bungalows.