Waimanalo beach is massive nearly 4 miles long. The beach park segment is located in the middle of the bay. The northern section is known as Bellows beach and used to be part of an air force base that has now closed down (used as a vacation spot for the military). The ocean here is rougher than Kailua Bay just to the north, making it less suitable for inexperienced swimmers, but the boogie boarding tends to be better. Despite less than ideal swimming conditions, the size, scenery, sand, and beautiful ocean colors make Waimanalo a great beach..