The most eco-friendly way to see Oahu, bicycle tours take you to Diamond Head, down Mt.Tantalus, and around Kualoa Ranch for an active and fun way to explore the island. Feel the wind rush past your face as you cruise downhill or pedal through a dirt trail. While you need to know how to ride to participate in these activities, the rides themselves are fairly easy, allowing you to focus on your environment and take in the sights.