Proposed as early as 1880, and surveyed along a more southerly alignment in 1883, the branch line to Waiuku was finally authorised in 1912, following the election of
William Massey, the local MP for Waiuku, as
Prime Minister. The first sod was turned on 19 February 1914, in a ceremony at Waiuku. Progress was slow, and the branch did not open until 5 January 1922, with more work to finish until the line was fully open. The line was not very profitable, and passenger services were withdrawn on 17 July 1948, being replaced by buses. In 1966 it was announced a new spur line would be built from Glenbrook to the
New Zealand Steel steel mill at Mission Bush. Traffic continued to decline, until the line was closed on 31 December 1967 to
Waiuku. The construction of the steel mill was the line's saviour. The spur line to the steel mill was opened on 7 October 1968. The remaining section from Glenbrook to Waiuku was in the process of being lifted until it was taken over by the
Glenbrook Vintage Railway (GVR). The line has been extended into Waiuku following the old branch as far as the last curve where it deviates. The line presently terminates at Victoria Avenue in Waiuku, a short walk from the centre of the town, with plans the eventually terminate the line at the Tamakai reserve, next to the old wharf. The extension to Victoria Ave was completed by Easter of 2010 with the first passenger carrying train running on the line on 3 April 2010, hauled by
JA 1250. The extension was officially opened to the public on Labour Weekend (23 October 2010) by Kevin Lawrence, former Waiuku Borough Mayor, and
Len Brown,
Mayor of Auckland.
Stations Helvetia and Patumāhoe opened on 10 December 1917, Mauku on 15 July 1918 for goods and on 10 May 1922 for passengers, when all the other stations opened. ==Services==