Cathedral Cove is an arched sea cave cut through a rhyolite headland at the southern end of Mercury Bay, connecting two sheltered white-sand beaches. The arch is large enough to walk through at low tide, and the setting — white cliffs, impossibly blue water, bush above — is as beautiful as New Zealand beaches get.
The walk in from Hahei is about 45 minutes each way through coastal bush on a well-maintained track. During peak season the track becomes very busy; kayakers can paddle in from Hahei beach and avoid the walk entirely. The marine reserve surrounding the cove protects remarkably clear water with excellent snorkelling around the rock platforms. No vehicles are permitted on the access road in summer — a shuttle bus runs from Hahei.