Tunnels Beach, also known as Makua Beach, is one of Kauais most exciting spots for swimming, snorkeling and scuba diving. What makes it so great is its large lagoon and its massive hook-shaped reef that provides protection from the surf. The reef here is so big, it can actually be seen from space. According to divers, its called Tunnels Beach because of all the tunnels and arches in the reef. But surfers often say its from the tubular or tunnel-shaped waves that are frequently found at this beach.