Although this dive site is considered relatively new to international divers, it is now recognized as one of the best dive sites in the world, offering divers a unique diving experience. The site is famous for its kelp forests, the sunlit yet turbulent water, the caves, and the many smaller marine life that inhabit the area. The dive sites are 17 miles offshore and make for a fantastic day trip of diving. The waters are nutrient rich and sub-tropical, providing most divers with a diving experience they would not have had before.
The water is colder than tropical dive sites, getting below 20 degrees and even colder in winter. Divers will have to dive with wetsuits all year round and on some occasions dry suit diving, although it is more technical, can be required.
Although the conditions of the dive site can be challenging sometimes, due to surge and current, divers of all levels and experiences can dive here.
The waters around Middle Arch are some of the most nutrient rich in New Zealand and so have over 120 different fish species. The islands are managed as a marine reserve and have been protected for decades. Fishing, along with feeding the fish, stepping onshore to the islands and removing rocks or shells are all prohibited and have allowed the island to blossom.
Middle Arch is one of the best sites to dive in the area with many chimneys, grottoes, caves, swim throughs, tunnels, and archways. The archway has a maximum depth of around 15 meters and has very colorful walls. The floor is made up of rocks and boulders and is home to many smaller marine life species. There is a sandy strip in the dive site that is home to stingrays, and there is a small cave that has a mirror air bubble at 9 meters. The outside wall, then falls beyond 30 meters deep.