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The Otira Viaduct just north of Arthurs Pass is impressive! Spanning 440m it was created to replace a narrow stretch of winding road known as the Devils staircase which is now a popular lookout spot. The Otira train tunnel which you travel through on the TranzAlpine is 8.5km long and runs between Arthurs Pass and Otira, the tunnel opened in 1923 and at that time was one of the longest in the world.
The Otira viaduct is to the south of Otira, between Otira and the Arthur's Pass summit. Completed in 1999 by McConnell Smith Pty Ltd, the 440 metres (1,440 ft) four-span viaduct carries State Highway 73 over a stretch of unstable land, replacing a narrow, winding, dangerous section of road that was prone to avalanches, slips and closures.