Located on the southwestern tip of the island, Aroa Beach is a beautiful stretch of white sand with insanely blue water, fringed by coral and rocks just a short distance from the shore. Definitely one of the top free things to do in Rarotonga! Set up a spot on the beach then all you need to do is swim out just a few metres. You don’t need to go too deep to start seeing some gorgeous marine life, and soon you’ll be surrounded by plenty of fish.