There is a narrow footpath which starts right of Ainsley Street. It leads to the forest, the barrow is located left of the footpath (barely visible from the footpath, since it is located above it on a small natural promontory). You can input the site's grid reference (NZ26434271) into http://www.gridreferencefinder.com to see location of the barrow in relation to the streets.
Something is not right. This message is just to keep things from messing up down the road