Heaphy Track Great Walk Credit The Heaphy Track, in the northwestern corner of the South Island, has undemanding gradients over 80km (around 50 miles) and takes around five days to complete. CREDIT: DOC/90 Seconds MetaData The Heaphy Track, in the northwestern corner of the South Island, has undemanding gradients over 80km (around 50 miles) and takes around five days to complete. CREDIT: DOC/90 Seconds