Starting at Kalapana, Hawaii you can walk for two hours to the place on the coast where active lava flows touch the ocean. This is insane.
Grand Wailea Canyon Activity Pool Maui, Hawaii wet playground's a destination in itself (9 pools at 6 levels (40 ft to sea level) connected by a river that carries swimmers along at varying speeds, lazy river currents to whitewater rapids. Highlights include 7 slides, grottoes, scuba certification pool, & Tarzan pool w/ rope swing. The world’s only water elevator swimmers are lifted to the surface in a sealed chamber. Epic.
The Westin Maui Resort & Spa, Hawaii, it's the best!
Inner tubing tour through the canals and tunnels of an old sugar plantation in Hawaii... Yes pleasee!