At the top of the Marlborough Sounds, the rugged, isolated roads of Rangitoto ki te Tonga/D'Urville Island are an increasingly popular mountain biking destination for a day or for longer.

The unsealed, largely 4WD-only roads make for great mountain biking trails suitable for standard mountain bikes and E-bikes. While not technical, the routes are steep and windy in areas and the mountain biking is considered at an advanced level, grade 3-5.

Much of the road is located within almost 6,000 hectares of public conservation land that was once a farm and now form the D'Urville Island Scenic Reserve. You'll pass through lush native forest and onto exposed ridges with sweeping views which, on a clear day, stretch across the sea to the Outer Marlborough Sounds and as far as Mt Taranaki.

There is no bike hire on the island, so bring your own on the water taxi or barge from Anaru/French Pass settlement. You can choose to be dropped off and picked up at Kapowai Bay or Catherine Cove. Ride one way or return, or stay at the Wilderness Resort in the cove. From the road near the highest point on the island, it's an exhilerating descent to your accommodation – or a grunty climb to start your day.

Another popular ride is across to the island's western side, to Moawhitu at Greville Harbour. Do it return from Catherine Cove or Kapowai Bay in a day, stay at the Department of Conservation's Moawhitu Campsite or pre-book the community hall at Kupe Bay.