Rimutaka Tunnel The first shot was fired in 1948 when the Public Works Department started the tunnel with bores of at the western end and at the eastern end. A contract for completing the tunnel was let to a consortium of Morrison Knudsen Inc. and Downer and Company on 7 May 1951. The work commenced at the west end in July 1951 and at the east end in August. The contract was expected to be completed in four years, but the headings met on 20 April 1954 with the concrete lining finished a month later. New Zealand Railways took possession of the
Mangaroa railway station on a tunnel through the Rimutaka Ranges. When the Rimutaka Tunnel opened in 1955, the line between Upper Hutt and Featherston then followed an alignment that bypassed Mangaroa altogether. The new Maymorn railway station on the Rimutaka Tunnel deviation was initially called "Mangaroa". Very little of the old railway formation remains between the west and east sides of the Mangaroa Valley. Cruickshanks Tunnel still exists, though there is no formal access to it and the status of public access is uncertain. The only remains of the old Mangaroa River bridge are a few wooden bridge piles. There is still a