These were later moved when a military stockade was built during the 1800's. Archaeo-astronomer, Alan Seath, has identified about 135 significant alignments onto Solar or stellar positions, coupled with overland mapping functions, originating from marked positions on these 36 Auckland hills. One hill uses another, more distant, hill or range as the target outer marker for a celestial event. A group of enthusiasts, researchers and media representatives assembled on Stockade Hill, Howick, before sunset on the 20th of March 2000 to witness the equinoctial Sun's descent into the trench on Mt. Wellington. The Sun's journey down to its age-old Equinox position was accompanied by the musical strains of a lone, Scottish piper, Bryan Mitchell.
All available evidence suggests a predominant astronomical usage.
These New Zealand astronomical alignment systems are an exact counterpart to surviving marker systems from Great Britain's Megalithic Age.