Tired of the same old gold-, white-, or black-sand beach? Then how about a green-sand beach? You'll need good hiking shoes or sneakers to get to this olive-green crescent, one of the most unusual beaches on the island. It lies at the base of Puu O Mahana, at Mahana Bay, where a cinder cone formed during an early eruption of Mauna Loa. The greenish tint is caused by an accumulation of olivine crystals that form in volcanic eruptions. The dry, barren landscape is totally surreal but stunning, as aquamarine waters lap on green sand against reddish cliffes. The surf is often rough, and swimming is hazardous due to strong currents, so caution is advised. Drive down to Ka Lae (South Point); at the end of the 12-mile paved road, take the road to the left and park at the end. Anyone trying to charge for parking is running a scam. Of course, lock your car and don't leave valuables inside. To reach the beach, follow the 2¼-mile coastal trail, which ends in a steep and dangerous descent down the cliff side on an unimproved trail. The hike takes about two hours each way and it can get hot and windy, so bring lots of drinking water. Four-wheel-drive vehicles are no longer permitted on the trail. Amenities: none. Best for: solitude.