reached home after dark in the winter and had to milk cows before and after school. John Pascoe said that some children spend "up to six hours a day travelling." Boys and girls were usually segregated. Infrastructure and mechanical Rail network The New Zealand rail network has around of line, of which about is electrified. At the network's peak in 1953, some of line was open. A 2009 study counted 1,787 bridges and 150 tunnels (totalling in length) on the rail network, but a 2011 study said there were 1,636 bridges, with a total length of and 145 tunnels, with a total length of . A 2021 Kiwirail report showed 106 tunnels and 1,344 bridges. Difficult terrain meant that some lines took years to complete, and has necessitated a number of complicated engineering feats, notably the Raurimu Spiral and Rimutaka Incline (the latter no longer in use). The network has been the subject of major upgrading works on a number of occasions. The biggest of these were the Westfield Deviation of the North Island Main Trunk from Auckland to Westfield Junction via Panmure and Glen Innes, opened 1930, the Tawa Flat deviation in Wellington, opened 1937; the Rimutaka deviation to the Wairarapa, opened 1955; and the Kaimai deviation in the Bay of Plenty, opened 1978. All of these involved major tunnelling works, of close to each in the two latter cases. Significant infrastructure improvements were also carried out on the North Island Main Trunk in the mid-1980s, some as part of the electrification scheme. As part of the 10-year Turnaround Plan announced in 2010, a number of regional lines were placed under threat of closure: all lines in Northland that form part of the North Auckland Line, the Stratford–Okahukura Line in Taranaki (mothballed since 2009), the northern portion of the Wairarapa Line, the Gisborne – Napier section of the Palmerston North - Gisborne Line (mothballed due to storm damage north of Wairoa early 2012, mothballed Napier – Gisborne from October 2012) As part of KiwiRail's 10-year long-term plan, most new capital will be spent on locomotives, wagons and the Auckland – Wellington – Christchurch freight corridor. Signalling Six signalling systems are used in New Zealand: automatic signalling rules (ASR), double line automatic (DLA), single line automatic (SLA), centralised traffic control (CTC), track warrant control (TWC), and station limits. Signals are of the colour light type and operate on speed signalling