Mārahau to Castle Rock Hut

Mārahau to Castle Rock Hut is a 15.1 km one-way point-to-point tramp: first along the Abel Tasman Coast Track to Tinline Bay, then inland on a sustained climb to the hut. Allow about 5½ hours for the walk and most of a day once you count stops. It suits trampers who want an overnight hut stop or have an onward route planned; it is not a short side trip from the coast. If you only want the coastal part, Tinline Bay is about 2.7 km from the start, then you can return the same way.

From Mārahau, follow the Coast Track for about 2.7 km to just beyond Tinline Bay campsite. Take the left fork onto the Inland Track. The climb begins gently on a well-formed, sandy tread through regenerating kānuka, broadleaf and fern gullies, then steepens markedly for about a kilometre. Small openings give you glimpses toward Anchorage and back across Tasman Bay.

About 4 km after the inland turnoff, a side track drops back toward the Coast Track near Anchorage. Keep toward Holyoake Clearing Shelter, roughly 15 minutes farther on. Beyond the clearing the tread is rougher, but the walking is mostly undulating with shorter climbs. Several stream gullies break up the last stretch to Castle Rock Hut, so expect a more uneven finish than the sandy lower climb.

The bush beyond Holyoake is less disturbed and includes rimu. Kākā and kākāriki are increasing in the park with Project Janszoon’s conservation work; listen for them as you move through the upper forest rather than expecting a clear view of the birds.

Castle Rock Hut sits in a small, relatively sunny clearing. It is a standard eight-bunk hut with heating, mattresses and a non-flush toilet; the tap water is untreated, and beds are first come, with no booking required. The nearby granite outcrops called Castle Rocks are about a 20-minute walk from the hut. They look over Mārahau Valley and Tasman Bay. From the outcrops, put one granite form in the foreground with the valley and bay beyond it; that gives the ridge view some depth. The short spur is eroded and locally difficult, so treat it as an optional extra; it is not included in the 15.1 km route.

The main Abel Tasman National Park car park is on Harvey Road, about 1 km beyond Mārahau’s waterfront. It has toilets and a map/information panel, and can fill in summer. There are few reliable water sources, especially between Tinline and Holyoake, so carry your own supply; treat water from the hut tap before drinking. Unbridged streams are generally crossable in normal flow but can become impassable in floods. Be ready to wait for water levels to drop, and expect wind and heavy rain to be possible year-round. Dogs are not allowed on the Inland Track.