Visitors will pay more for four of the country's great walks

International visitors will pay roughly double for DOC huts and campsites on New Zealand's four most popular Great Walks as part of a trial starting in October.

The increased fee aims to help DOC maintain the tracks and control visitor numbers.

A price hike would affect tourists using the Milford, Kepler, Routeburn and Abel Tasman Coast tracks.

Conservation Minister Eugenie Sage said the nine Great Walks were premier tracks with spectacular scenery and were a "magnet for international visitors".

"The seven-month trial from October 2018 to April 2019 will provide information on the effectiveness of pricing as a tool to manage visitor pressure," Sage said.

"It is also part of setting and maintaining a fair pricing system for New Zealanders."

The Department of Conservation's (DOC) investment in maintaining nine Great Walks exceeds the revenue made from users' hut fees by up to $3.8 million each year.

"DOC expects to recover up to an additional $2.9 million during the trial period, without significantly reducing bookings and visitor demand," Sage said.

The increased accommodation fees might also encourage overseas visitors to use less visited Great Walks where prices remain the same, she said.

Prices for huts for international visitors, including children, on the Milford Track will be $140 per night, on the Kepler and Routeburn $130 per night and Abel Tasman Coastal Walk $75 per night.

Hut prices for New Zealanders remain at $70 per night for the Milford, $65 per night for the Kepler and Routeburn, and $38 per night for the Abel Tasman Coastal Walk.

New Zealanders under 18 will remain free of charge.

"The year ending March 2018 was another record year for visitor numbers to public conservation land, with 1.75 million people, or 52 per cent of all international tourists visiting a national park last year, up 5 per cent on the previous year," Sage said.

"International visitors currently make up around 60 per cent of all those walking and using the Great Walks.

"Under the trial, fees for international visitors will be about double current rates on the Milford, Routeburn, Kepler and Abel Tasman Coast walks."

Great Walks would remain free of charge for New Zealand children to encourage tamariki to engage with their natural heritage, she said.

Bookings for New Zealand's nine Great Walks will open over a two-week period for the 2018/19 season, beginning 12 June 2018.

This year DOC would roll out a new booking system which will enable people to manage their bookings and allow them to receive timely health and safety information.

Details of when bookings open for each Great Walk are on DOC's website. DOC's new booking service will be introduced in phases, beginning with Great Walks.