Activities · Destination Guide

Mercury Islands Coromandel New Zealand

Wild kelp forests and predator free islands off the Coromandel coast

Updated Nov 21, 20259 sources

View On Map

Mercury Islands (Coromandel Peninsula) Activity Planning

Pick an activity mode to compare signature sites, skill fit, and gear planning notes before you lock your trip.

Scuba

What It Feels Like

For certified divers the Mercs pack a lot into a compact area: sheltered bays ideal for training, caverns and arches, walls plunging past 30 m and offshore pinnacles that draw kingfish, trevally and big schools of blue maomao. Dive Zone Whitianga and other local charter operators run day boats that choose sites based on swell and wind, so you can usually find a lee even when the forecast looks marginal. This is classic New Zealand temperate diving with a strong conservation story layered on top.

Signature Sites

Start Here

  • CORALIE BAY - GMI

    A large, mostly sheltered bay on the eastern side of Ahuahu with extensive kelp reef, rocky walls and sand patches that drop towards {{ 30 | distance:m }} at the entrance.

  • THE CATHEDRAL

    On the northern side of the Mercs, The Cathedral combines a sheltered inner bay of sand and broken kelp with outer walls, boulders and pins that catch swell and current.

  • WEST POINT

    On Cuvier Island, often combined with extended Mercs and Aldermen trips, West Point offers clear blue water, steep reef and big fish potential when conditions and permits align, giving a taste of truly offshore New Zealand diving.

Advanced

  • THE BOOK CASE - GMI

    On the northwestern side of Great Mercury, The Book Case is an advanced wall dive with a near vertical face in the {{ 25 | distance:m }} to {{ 30 | distance:m }} range, frequent current and big fish potential.

  • Never Fail Rock - GMI

    An exposed pinnacle in open water, suited to experienced divers comfortable in strong current and blue water ascents.

Planning Playbook

Operator Checklist

Base yourself in Whitianga for easy access to Dive Zone Whitianga and other local charters that run day trips to Ahuahu and, in good weather, the outer Mercs and even Cuvier or the Aldermens. Summer weekends book out, so reserve boat spots and rental gear well ahead, especially around New Zealand public holidays. Bring your cert cards and logbook, and expect skippers to ask about recent cold water experience before putting you on advanced sites. Caulerpa rules mean you cannot take any marine life from the Great Mercury Island zone and must thoroughly wash and dry all gear between locations.

Conditions Fallback

  • Base yourself in Whitianga for easy access to Dive Zone Whitianga and other local charters that run day trips to Ahuahu and, in good weather, the outer Mercs and even Cuvier or the Aldermens. Summer weekends book out, so reserve boat spots and rental gear well ahead, especially around New Zealand public holidays. Bring your cert cards and logbook, and expect skippers to ask about recent cold water experience before putting you on advanced sites. Caulerpa rules mean you cannot take any marine life from the Great Mercury Island zone and must thoroughly wash and dry all gear between locations.

Avoid

  • Base yourself in Whitianga for easy access to Dive Zone Whitianga and other local charters that run day trips to Ahuahu and, in good weather, the outer Mercs and even Cuvier or the Aldermens. Summer weekends book out, so reserve boat spots and rental gear well ahead, especially around New Zealand public holidays. Bring your cert cards and logbook, and expect skippers to ask about recent cold water experience before putting you on advanced sites. Caulerpa rules mean you cannot take any marine life from the Great Mercury Island zone and must thoroughly wash and dry all gear between locations.