The Otago peninsula was formed entirely by volcanic activity and the tall polygonal columns featured on this walk are remnants of this past. As molten lava cooled slowly beneath the hardened crust, it contracted and formed geometrical cracks which propagated downwards as the mass cooled. The Giant's Causeway in Northern Ireland is the most famous example of this phenomenon.
Access
The Organ Pipes Walk begins at a small car park on the Mt Cargill Road north east of central Dunedin. To reach the car park take the North Road through the North East Valley as far as Norwood Street. Follow Norwood up the valley and turn onto Upper Junction then Mt Cargill Roads. Continue for 2-3km; the car park is signposted on the left beyond the Mt Zion quarry. There is a healthy crop of rhubarb here and room for one or two cars.
Car park-Organ Pipes: ½ hr, easy
The track climbs up steps composed largely of fallen columns. After passing a track junction to the Mt Cargill Walk, you will come upon a scree slide of columns where there was once a viewing platform. There is a good view of the Organ Pipes from here.