Without a doubt my favorite beach in Waikiki, the Fort DeRussy Beach Park offers slightly less crowded ocean access than Kapiolani and Kuhio Park Beach, as well as volleyball, tennis, and pickleball courts, ample greenspace for frisbee, catch, flying kites, etc., as well as picknick tables and walking paths! Founded on a historic military fort (hence its name), the park also consists of Battery Randalph, which houses the U.S. Army Museum of Hawaii (open Tuesday – Saturday, 10am-5pm, free admission).
Whether sunbathing, swimming, kicking back with a pina colada, or generally just enjoying the beach, this location provides excellent views of the ocean, Diamond Head, and other beachgoers. I recall specifically a man with his dog named “Roxy” would always play frisbee here around 3:00 or 4:00pm (at least on Saturdays!) There is also a surfboard and kayak rental on sight which puts out complimentary beach lounge chairs during the daylight hours!