Because of the clarity of the water and the variety of marine life, Kealakekua Bay has been designated a marine preserve. The Captain Cook Monument across the bay was erected in 1874 by the British to mark the spot where Cook was killed.
The spot is marked by a submerged plaque that can be seen through the water, but it is accessible only by boat.
It is located along Hwy 11 near the town of Napoopoo.