The rock walls of dozens of ancient fishponds—a pinnacle of Pacific aquaculture—can be seen for miles along the shoreline from the highway between Kaunakakai and the East End. The U-shaped lava rock and coral walls contain mākaha (sluice gates) that allowed smaller fish to enter, but trapped them as they grew larger. Some are still in use today; join volunteers with Ka Honua Momona in restoring the 15th-century Alii Fishpond, a half-mile west of One Alii Beach Park and once reserved for kings, and Kalokoeli Pond, another 3 1/2 miles east.