In 2011 Tim Prebble knocked on the door of a Canadian bike park developer and asked them to build one in Christchurch.

Five years later, work has begun on the $20m Christchurch Adventure Park in the city's Port Hills.

The park, the biggest of its kind in the southern hemisphere, is expected to open in December.

PORT HILLS LEISURE A birds-eye conceptual rendering of the Christchurch Adventure Park in the Port Hills.

Prebble, a Christchurch mountain biker, was cycling at a bike park developed by Select Evolution in Whistler, Canada in 2011 when he decided to pitch Christchurch as their next investment destination.

"If you don't ask, you don't get."

Within three months Select Evolution founder and chairwoman Fiona Sutton was in Christchurch talking to the McVicar family, which owns the land the park is being developed on.

SUPPLIED Select Evolution president Fiona Sutton at the Whistler Bike Park, a model for one planned for Christchurch.

Prebble said getting to this stage has been a "rollercoaster ride" for everyone involved, but he could not wait to see the park finished.

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Local contractors have been engaged, all 36 resource consents are in place and Select Evolution now has all the funding it needs, including a $2 million investment from the Christchurch City Council, another $2m from the Government. Other funding has come from the Christchurch-based New Urban Group, a bank loan and additional investment from the United States, Singapore and New Zealand.

The park, located on 358 hectares of forested land between Dyers Pass, Worsleys and Summit roads, would include more than 100 kilometres of downhill mountain bike routes, a 1.8km chairlift that would take people up 435 vertical metres, 2km of zip lines through the forest, rock climbing, and a cafe bar seating up to 180 people.

Construction of five lodges, and 14 cottages accommodating 252 people and a mountain coaster, would be built in stage two.

Sutton said on Thursday, she expected those two aspects to open within two or three years.

The park would employ a 120 full-time and part-time workers

Sutton said a December opening was a tight time frame, but she believed it could be achieved.

Contractors hoped to get the concrete for the chairlift towers poured before winter and the towers would be installed in the spring.

"They're being manufactured in Austria as we speak."

Christchurch Mayor Lianne Dalziel said the development was the first real private public partnership to happen since the quakes.

"It just shows what can be achieved when we work together in partnership - so much more than when we stand to the sideline and do not commit that investment."