Daylighting (tunnels)

Daylighting a tunnel is to remove its "roof" of overlying rock and soil, exposing the railway or roadway to daylight and converting it to a railway or roadway cut. Tunnels are often daylighted to improve vertical or horizontal clearances—for example, to accommodate double-stack container trains or electrifying rail lines, where increasing the size of the tunnel bore is impractical.

List of daylighted tunnels

The Moocomonga Tunnel carried the Central Western railway line through the Gogango Range in Queensland, Australia. It opened in 1876. The tunnel was daylighted in 1983 due to rock falls which blocked the tunnel from time to time.
The Coromandel and Pinera Tunnels on the Belair line in Adelaide, South Australia, both built as a single track tunnel with the line in 1883, were daylighted in the 1920s when the line to Belair was duplicated.
The Arncliffe Tunnel on the NSW South Coast Line was daylighted and replaced with a road bridge when the track was quadruplicated in 1921
The Waterfall Tunnel on the NSW South Coast Line was daylighted in 1914 when the line was duplicated.

The railway line through the Manawatū Gorge, when constructed in 1891, had five tunnels. Three of these were daylighted in 2008 to allow for the carriage of large containers.
The Macgregor Tunnel on the Main South Line was daylighted in 1971 to allow for container freight.* Tunnels No. 22 and 23. were daylighted in 1981 and 1979 respectively on the Main North Line.
The Mercer Tunnel was daylighted in 1956 on the North Island Main Trunk.
The Makohine Tunnel was daylighted in 1984 on the North Island Main Trunk.
The Kiwi Tunnel was daylighted in 1972 on the North Island Main Trunk. This alignment has since been bypassed in 1985 however.

* Liverpool Lime Street station was originally approached through a twin-track tunnel completed in 1836. The tunnel was daylighted in the 1880s, and replaced with a deep four-track cutting, with only the eastern approaching Edge Hill railway station remaining as a tunnel.

Auburn Tunnel on the Schuylkill Canal, daylighted in 1857
Tunnel No. 5 on the Alaska Railroad's Seward-Anchorage line
Tunnel No. 5 on the Virginia & Truckee Railroad at Nevada S.R. 341 near Virginia City
The on the North Pennsylvania Railroad, near North Wales, Pennsylvania, built as a tunnel between 1853 and 1856, daylighted in 1930 when the Reading Railroad electrified the line
A number of tunnels were open cut for the National Gateway project including:
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