Built at a cost of £3 million by a joint venture consortium of NZ's Fletcher Construction Ltd, and the American Henry J. Kaiser Co., Inc., the 1.9 km tunnel involved the use of 250 kg of explosives to remove 150,000 cubic metres of rock. It was then lined with 1.5 million glazed white tiles.
Opened on the 27th of February 1964 by Brigadier Sir Bernard Fergusson, last British Governor General of New Zealand, the tunnel replaced a tortuous route over Evans Pass on the Port Hills.
Note: the artist's rendition in the 1962 promotional illustration at the top bears little resemblance to what eventuated.
An elevated southerly view of the Heathcote entrance to the tunnel, showing the toll gates and administration building.