This protected bay makes it a haven for fish of all kinds and an excellent spot for snorkeling. 'Ahihi-Kina'u is actually a natural area reserve, first designated in 1973; it is not a recreational park. No fishing is permitted at any time, but you are permitted to snorkel here. According to DLNR, access to the northern and most often visited portions of the reserve will be allowed during posted visiting hours of 5:30 a.m. to 7:30 p.m. daily.
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.
Ahihi Bay is located about 5 miles outside of Kihei and about a mile from Big Beach (Makena Beach) along Makena Alanui Road. There are no showers and no lifeguard is on duty. There is a $5 non-resident fee per vehicle. The charge is used for upkeep, maintenance, infrastructure costs, and reserve protection projects.
When the waves come directly into the bay it is too dangerous to snorkel, so stay out of the water. 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.
At times, 'Ahihi Kina'u Natural Area Reserve has been a victim of too much visitation
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 swum in them, leaving behind their sunscreen on the water.
Please do NOT touch any of the turtles, as you can deliver infections to them through human touch. Large tarpon has also been seen here, often being mistaken for a small shark.
New user-fee for non-Hawaii residents now in effect
As of October 1, 2020, 'Ahihi-Kina'u Natural Area Reserve will now charge non-Hawai‘i residents a user-fee of $5 per vehicle. Two machines located within the reserve's parking lot will accept credit or debit cards and produce the receipts that must be displayed on their dashboard while using the area. Use-fees paid by visitors will help pay for infrastructure costs and/or projects that protect the reserve's unique natural resources. Hawaii residents will not be charged but must still display a daily pass that will be generated from the same machines.
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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. We recommend visiting early before the parking lot fills up when possible. There is no parking outside the designated stalls in the parking area. All cars parked on the road's shoulder will very likely be ticketed and/or towed by local authorities.