I love "The Big Island" of Hawaii for its diversity. When you land there at the airport, you're in a huge,ancient lava field, and it's quite a desolate landscape! A few miles away, there are areas of lush rainforest, and also the stunning Mauna Kea that can become snow-covered in winter. Kileaua volcano is an active volcano (constantly since 1983) and the National Park is a great place to hike and sight-see. At the other end of the island from the volcano, the beautiful cliffs at Pololu Valley are breathtaking. Hapuna Beach is one of the best swimming beaches in Hawaii, located just north of Kailua-Kona. You should see as many of the Hawaiian Islands as you are able, but my favorite is definitely The Big Island.