There is about 5km of fun flowy grade 1 and 2 singletrack in the forest. There are no big hills - it's a great area for beginners to improve in. There's fun stuff too with some jumps and drops but all are easily avoidable.
Turn off SH1 in Oamaru into Derwent St, go up the hill then veer right into Reservoir Road. Just past the water tower, you will see a car park on your left.