The project could swap ramblers for skiers

But despite the proposed building's size, only 20m of it would be visible above ground.

It is claimed the development, which also includes plans for a 400-bed hotel, could create 700 full-time jobs in a hard-hit area of north Wales's economy.

The former Glyn Rhonwy quarry, which is a mile outside the national park, is one of many sites under consideration for the scheme.

Caernarfon AM Dafydd Wigley said he supports the initiative even though it will require financial support from the assembly.

The company behind the development is a consortium of six local businesses and an overseas firm.

Snowdonia needs to bring the visitors back

It said there is nothing similar to the proposed project in the world at the moment, although work is starting soon on a similar project in Australia.

A spokesman said they needed to push forward with planning permission soon as other sites were under consideration, including one in Sheffield.

Mr Wigley chaired a meeting in Llanberis on Thursday morning to announce the scheme, although councillors were briefed on Wednesday evening.

An application for planning consent is due to be put forward.

Public backing

However the size of the development and the environmental importance of the locality mean it could become a matter for the assembly, which has the power to call in the project for assessment.

In December 2001 plans were unveiled to revamp the cafe complex and former hotel on the top of Snowdon, the highest mountain in England and Wales.

A consultation process began in January with public meetings in Llanberis and Beddgelert to gauge whether there is public backing for the �4m proposals.