Plans are under way to open the historic Ongarue tramway as a rail trail that visitors can walk or bike, modelled on the highly successful Otago Central Rail Trail.

The Department of Conservation (DoC) is billing the tramway, which would be known as the Central North Island Rail Trail, as an untapped resource in the Ruapehu region and describes the trail as 60m of back country adventure.

The route links the historic logging settlements of Ongarue and Pureora.

From 1922 to 1957 the Ellis & Burnand operation at Ongarue was a major Central North Island timber industry operation.

The company was one of the largest native timber companies in the country and almost certainly the leading producer of rimu timber.

Doc archaeologist Neville Ritchie says Ongarue was the longest bush tramway still in original condition and the best rail trail opportunity for further development, after Otago.

"It will be an adventurous back country trail through a unique part of New Zealand," Dr Ritchie said.

"It's an important part of New Zealand's pioneer rail and timber industry heritage."

The old tram route has numerous cuttings, embankments and stream crossings and winds through natural bush.

The spiral is one of the most spectacular sections.

In its former state it comprised a lower-level bridge, a very deep cutting, a curved tunnel, a complete circle of track and an over-bridge.

Dr Ritchie said the trail featured ignimbrite rock formations and bluffs and extensive native forest, including the tallest recorded totara in New Zealand.

The tramway was identified as a DoC heritage icon site, one of 12, chosen in part for its ability to tell stories about the Kiwi identity.

The track would be built in five stages and would include replacing eight bridges.

The first three stages of 30 km would be undertaken over 2009/2010 and follow the tramline from Ongarue to Piropiro Flats where there is an existing camping area.

Stage 4 and 5 would take place over 2010/2011 would extend the trail the final 30 km from Piropiro Flats to Pureora Village DoC has a visitor office and cabins.

The rail trail project will be complimented by an eco tourism venture, Pa Harakeke, by the Maraeroa Corporation and a proposed tree canopy Skywalk at Pureora by two other trusts.  In the south opportunities for accommodation, transport and saw-milling heritage projects are being explored.