Poolburn Gorge

The Poolburn Gorge is a gorge located in the Central Otago region of the South Island of New Zealand, 4 km east of the small settlement of Lauder. The Ida Burn flows through the 2.5 km long canyon across the Raggedy Range between the Ida Valley and the Manuherikia Valley. There are no public roads through the gorge; only the track of the former Otago Central Railway, now used as the Otago Central Rail Trail, follows the river on the southern flanks of the gorge.

The landscape surrounding Poolburn Gorge is barren and dry, shaped by the typical Central Otago climate of dry hot summers and cold winters. The gorge cuts through schist rock bluffs, with the vegetation on the steep slopes consisting of tussock and hardy low-growing shrubs. Contrasting this, a ribbon of lush trees lines the immediate river banks at the bottom of the gorge. The Ida Burn joins the Manuherikia River shortly after it emerges from the Poolburn Gorge into the Manuherikia Valley.

The Pool Burn was known to southern Māori as Te Waipapapa o Karetai - the water container of Karetai, a Ngāi Tahu chief.

The Poolburn Gorge section of the Otago Central Branch Railway encompasses two bridges and two tunnels, and gently snakes along the true left (south side) of the gorge. The construction of the railway line through the gorge took over three years, with up to 300 workers employed at the peak of construction around 1902.

At the eastern entrance to the gorge, the 37 m (121 ft) tall Poolburn Viaduct is the highest bridge on the rail line, and is bridge No.69 starting from Dunedin. Built from 1901 to 1904, the 108 m (354 ft) long viaduct was the last big masonry pier bridge with steel trusses built on the line. It has the longest center span on the Otago Central Railway at 47.5 m (156 ft) long. Schist quarried from outcrops close by was trimmed and bolstered to construct the piers and abutments with the help of large gantry hoists to lift and position the stone slabs.

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Wikipedia