The construction of the original Wellington to Masterton railway was authorised by the New Zealand Government in 1871, one of a number of key railway schemes built during the term of Julius Vogel, Colonial Treasurer. The extension of the Wellington to Upper Hutt line to Kaitoke and Summit involved three tunnels, extensive earthworks and three sections of steep gradients – conforming to conventional railway standards of the time. The section of line from Upper Hutt to Summit was built by the Public Works Department and also under a number of private contracts commencing in 1874. The line from Upper Hutt to Kaitoke was opened in 1877, and from Kaitoke to Featherston, via Summit, in 1878.

The most challenging part of the railway was locating a route to descend from Summit to the Wairarapa plains, due to the steep and rugged topography on the eastern side of the Rimutaka Ranges. A steep three-mile (4.8km) incline of average 1 in 15 gradient was located between Summit and Cross Creek, worked by Fell locomotives. A centre-rail was used for both adhesion of ascending trains, and for braking for descending trains. The Fell locomotives were equipped with a centre engine, with horizontally-mounted driving wheels that made contact with running surfaces either side of the centre rail.  It was the third and last Fell system built, and the longest-lasting out of the systems at Mont Cenis in France, and the Cantagalo railway in Brazil.

A replacement tunnel under the Rimutaka Ranges was mooted as early as 1900, deferred due to cost, and proposals were revisited in 1921-22 and in 1936-1939, the latter project deferred due to the onset of World War II. The maintenance costs associated with the Incline and aging Fell locomotives continued to increase. In 1945 the project was revisited, plans finalised and approved. The Public Works Department and Morrison Knudsen Inc. and Downer and Company constructed the Rimutaka and Maymorn tunnels and associated deviation from 1951-1955.

The old line over the Rimutaka Incline was closed on 29 October 1955, the new line opening a few days later on 3 November 1955. The railway and structures on the old route were dismantled, demolished and sold shortly after the line closed. Bridges were retained to provide continued road access into the area, land to the west of Summit passing into water works and Greater Wellington Regional Council ownership, land to the east to the Department of Conservation.