Backcountry and Long-Distance Mountain Bike Routes

Whites Bay and Mount Robertson Mountain Biking Blenheim: Technical DOC Loop

Last updated November 2026

Above the beach at Whites Bay, the Whites Bay and Mount Robertson mountain bike tracks climb into Mt Robertson Scenic Reserve on a network where, in DOC’s words, “tracks range from tight technical downhill tracks to rocky native single track”.

At its heart is the Mount Robertson Loop Track, 7.1 km and graded 3 to 4 (intermediate to advanced), which most riders ride anticlockwise from either of two access points on Port Underwood Road.

From the loop you can push on to the 1,036 m summit, or drop down the expert-grade Pukaka Valley. DOC warns that the tracks are narrow and technical in places, and Marlborough NZ says much of the clay track is unrideable when wet.

Practical Information

Start
Either of two signed access points on Port Underwood Road, or ride up from Whites Bay on the Black Jack Track mountain bike section
Distance from the city
Whites Bay is 15 km from Tuamarina on State Highway 1 (DOC)
Mount Robertson Loop Track
7.1 km; grade 3 to 4 (intermediate to advanced); most ride it anticlockwise
Summit Route
6.4 km return from the loop junction at about 700 m; grade 3 to 4; no water
Pukaka Valley extension
Grade 5 (expert); mostly ridden downhill
Black Jack Track section
1.9 km, about 20 minutes; grade 3 to 4; uphill only on the left-hand branch
Water
None on the summit route; carry your own
Fires
No open fires at East Coast reserves
Managed by
Department of Conservation
Status
Check DOC’s Mount Robertson tracks page for current closures before you ride

Where to find it

Whites Bay and Mount Robertson Mountain Biking Blenheim
Map of Whites Bay and Mount Robertson Mountain Biking Blenheim

Get directions

About Whites Bay and Mount Robertson Mountain Bike Tracks

Whites Bay has a near-flat sandy beach and a camping area, and the forested hills behind it rise to Mt Robertson. DOC manages the tracks in Mt Robertson Scenic Reserve as shared walking and riding routes, and it is upfront that they are narrow and technical in places.

Marlborough NZ describes the ride as a 12 km loop, or 21 km if you add the summit, and warns that much of the clay track is unrideable when wet. Plan around the weather: DOC says hot, dry conditions and strong, cold winds are common here, and wasps can be a problem, especially in late summer and autumn.

The summit route is a ride in its own right. It leaves the loop at a junction at about 700 m and follows a ridge through beech forest to the top of Mt Robertson at 1,036 m, 6.4 km return. There is no water on the way, so take enough with you.

Trail Grades and Direction

Mount Robertson Loop Track

The loop is graded 3 (intermediate) and 4 (advanced). DOC says most mountain bikers ride it anticlockwise, and it is well signposted.

Black Jack Track mountain bike section

Riders starting from Whites Bay can climb to the loop on the Black Jack Track’s 1.9 km mountain bike section, graded 3 to 4 and about 20 minutes’ riding. DOC’s rule is clear: looking uphill from the Whites Bay end, you must only travel uphill on the left-hand branch.

Pukaka Valley

The Pukaka Valley extension is graded 5 (expert) and mostly ridden downhill off the loop. DOC describes it as extremely narrow and technical in places, and warns riders to expect walkers coming uphill. The valley track has unbridged stream crossings.

Getting There

DOC’s route to Whites Bay leaves State Highway 1 at Tuamarina and heads east on Hunter, Pembers and Rārangi Roads, 15 km from Tuamarina in all. From Picton, Port Underwood Road is a 41 km drive that DOC describes as winding and unsealed.

The loop’s access points are on Port Underwood Road. For the Pukaka Valley, Pukaka Road leaves Pembers Road about halfway between Tuamarina and Rārangi, and the car park is 17 km from Blenheim.

Where to Learn More

Department of Conservation: Mount Robertson tracks: the loop, summit route and Pukaka Valley extension, with grades and alerts. Track information: Crown Copyright: Department of Conservation Te Papa Atawhai 2026. Licensed under CC BY 4.0.

Department of Conservation: Whites Bay tracks: the Black Jack Track mountain bike section, the uphill rule and current track alerts.

Frequently Asked Questions

How long is the Mount Robertson Loop Track?

DOC gives it as 7.1 km. Marlborough NZ describes the full ride as a 12 km loop, or 21 km with the summit.

How hard is it?

The loop and summit route are graded 3 to 4 (intermediate to advanced), and the Pukaka Valley extension is grade 5 (expert). DOC says the tracks are narrow and technical in places.

Which way should I ride the loop?

DOC says most mountain bikers ride it anticlockwise.

Can I ride up from Whites Bay?

Yes, on the Black Jack Track’s 1.9 km mountain bike section, but only uphill on the left-hand branch.

Can I ride when it is wet?

Marlborough NZ says much of the clay track is unrideable when wet, so wait for dry weather.

Is there water on the track?

Not on the summit route, so carry all you need.

Can I light a fire?

No. DOC does not allow open fires at East Coast reserves; only portable stoves can be used for cooking.

Spotted something incorrect on this page? Let us know.