You are lucky the sun only rises and sets once a day on Hawaii—otherwise, you’d spend all of your time transfixed by the horizon. Hike to the leeward (eastern) side of any island on a clear evening and train your eye over the ocean in search of the “green flash,” an optic phenomenon in which a green sliver of light hovers in the wake of the setting sun. (On Oahu, the remote Kaena Point is a good spot to see the flash.) Sunsets on Kauai, “The Garden Island,” make the beauty of the coastal surroundings even more poignant. If you rise early and tackle the Lanikai Pillboxes trail on Oahu or summit the volcano at Haleakala National Park on Maui, you'll experience an unforgettable morning as the sun rises over the ocean for a new day.