This protected bay makes it a haven for fish of all kinds and an excellent spot for snorkeling, but the area has become another victim of popular guidebooks. Ahihi Kina'u is actually a natural area reserve, not a recreational park.
Many of the hikes are over treacherous, barren, hot and remote a'a lava and through sensitive land of historical and ecological nature. As a result there has been a lot of damage to archaeological sites. The fragile anchialine pools, home to unique species of brine shrimp endemic to Maui, have been threatened by visitors who have actually swam in them, leaving behind their sunscreen on the water. The bay is relatively shallow, less than 15 feet, or about 100 feet from shore. The bay gradually gets deeper, but not more than about 25 or 35 feet. Snorkeling off to the left (east) shows off the extensive coral formations. There are sand trenches and shallow caves in convoluted canyons near the shore. A little further out, where the coral has fewer deep cuts, are numerous Hawaiian Green Sea turtles. Please do NOT touch any of the turtles, as you can deliver infections to them through human-touch. Large tarpon have been seen, often being mistaken for a small shark. When the waves come directly into the bay it is too dangerous to snorkel. The bay is very shallow and there are large rocks all over the place. The current isn't too bad until you get way outside the bay. Parking is a bit far away from the bay, so do not leave any valuables in your car or unattended. That all said, we advise people show some aloha and skip this location.
Ahihi Bay is located about 5 miles outside of Kihei and about a mile from Big Beach (Makena Beach) along Makena Alanui Road. Take Wailea Alanui Road until it becomes Makena Alanui Road, drive past Big Beach. You will pass several parking lots and residential houses and condos. On the right, about a mile from Big Beach, is a sign with 'AHIHI-KIANA'U NATURAL AREA RESERVE printed on it. The main parking is along the road or in a gravel lot past the last of the residential houses, a few yards after the end of the stone wall. The road passes very close to the water, with a stone wall about 10 feet high on the seaward side of the road. Boulders line the road, keeping the sea from washing the road out. Do not block the road or any driveway.