Makohine Marvel (Rangitikei) Traditional Cache

This cache is located at a popular rest stop, where one of the icons of the Main Trunk Line can be seen.

The Makohine Viaduct is the first high structure crossed by northbound trains as they make their way up the Rangitikei River from Marton to Taihape, and the seventh tallest Viaduct in New Zealand at 72 metres high, and 227 metres long. Its site was located by J T Stewart when he carried out the location surveys in 1886. No practicable bypass was available, and construction methods of the day were not equal to building an earth embankment across the Makohine Valley.

Design of the Makohine Viaduct began in 1893, as construction of formation for the line approached the site where it would be built. Site clearance for the foundations began in June 1896. When tenders were called for construction of the viaduct and bids opened, they were found to be much higher than expected. Following a review, and in light of the success of the co-operative labour contracting scheme set up by the Public Works Department (PWD) at the government’s behest, the decision was made to build Makohine using PWD supervisors and co-operative labour contractors. This came about through dissatisfaction at the level of expertise, resources, and performance of conventional contractors.

A steel fabrication factory was built on flat land south of the tunnel that formerly led to the viaduct. (The tunnel has subsequently been daylighted.) Labour unrest in England caused delays of two years in delivery of the machinery required for the fabrication factory. Electric lighting was installed in the factory and at the viaduct site so that once the factory could commence work, double-shift working could speed progress. Erection of steel for the first pier began in April 1900. The first train crossed it on 9 June, 1902, with the official opening being held on 17 June.

Makohine has a form unique among the central North Island viaducts of its period. The centre span cantilevers beyond the two piers to support sidespans that are shorter than the distance between pier and abutment. This overcame the need to found piers in the steep and unstable sides of the Makohine Valley. Thus the main foundations are secure from slips or erosion of the valley walls. A disadvantage of this form of construction was that extensive timber staging had to be built to support the spans until they could be self-supporting, an expensive and time-consuming task.

Like the other central North Island viaducts, it was successively modified in 1925-32, and again in 1983-89 to permit it to safely carry heavier and more powerful locomotives. Intermediate vertical members were added to the Warren trusses of the main spans and some key steel members were strengthened by welding on additional plates to increase their load carrying ability. In the later period, the main changes were to replace timber way-beams with steel and to provide stronger links to carry traction and braking loads into the main structure of the viaduct. At the same time, brackets were added to one side to carry concrete masts for electrification of the route.

During 2008 - 2011, the Viaduct played host to a $14 million safety and ease of access project for State Highway One, which involved realigning 4 kilometres of highway to eliminate the level crossing, the black spot road winding up Makohine hill, and yet at the same time improving and preserving this picnic spot (read about it here). In March 2011 an IPENZ plaque was unveiled at the Makohine Viaduct, recognising its important place in the engineering heritage of New Zealand.

Cache Details

The cache is unusual, a mag strip. Please sign in small writing on the 'white side'. It is located on the Armco guard-rail barrier, along from the entry to the picnic spot. Please use caution since this is the main highway of the country, but there are normally also substantial gaps in the traffic that will allow you to retrieve the cache without fuss. Please take care to attach it back to the Armco exactly as you found it. Easiest to enter the parking heading North towards Taihape.