The final section of the Dun Mountain Trail runs alongside Nelson's water pipeline, joins the Maitai Valley Road for a short distance before climbing back over Tantragee Saddle to join back up with the Dun Mountain Trail in Codgers, where you originally started your ride. Alternatively, you can stay on Maitai Valley Road for an extra 1km then join the Maitai Walkway and follow that all the way to Nelson CBD.
As you pass the Maitai Dam on your right hand side stay left and follow the trail along the water pipeline. After about 2km the trail forks, stay right (left goes up-hill), following the trail down to Smith's Ford on the Maitai Valley Road. Turn left when you meet the road and carry on down it for approximately 2km. Immediately as you pass the camp site entrance you will see a left turn that leads to a small bridge over the river.
Go over this bridge, over the gate and follow the fire road climb all the way up the hill (it gets a bit steep in places but is soon over). You will ride past the water settling ponds and up anther steep pinch to the top. At the crest of the hill you'll see a gate on your left, and a gate straight ahead to your right. Go through the left gate and down the hill all the way back to Brook Street.
About 2km past the campground you can take a left turn (just before a narrow bridge) and get onto the Maitai Walkway. This is a shared path so please be courteous to walkers. Following this track take you right into Nelson. Alternatively, if you left your vehicle at Brook Street you'll need to exit the trail as it enters Nelson and ride.