Residents and campaigners in the Perthshire town of Blair Atholl have told MSPs their area should be included in the Cairngorm National Park.
MSPs have been gauging opinion on the Cairngorms national park
The park, established three years ago, is the biggest in the UK and stretches from Grantown-on-Spey in the north to the Drumochter Hills in the south.
Nationalist MSP John Swinney has lodged a bill to extend the southern boundary.
Holyrood's environment committee met in Blair Atholl to gauge local opinion on the proposal.
Under Mr Swinney's bill, the new boundary would include the town as well as the Beinn Udlamain hills and Spittal of Glenshee, increasing the park's area by another seventh and adding some 700 people.
The MSP for North Tayside said the park's current area had effectively sliced several important mountains in two.
He also claimed ministers had given in to pressure from Highland Council in 2003 to exclude the southern areas, despite the fact that they were originally included on Scottish Natural Heritage's proposed map of the park.
However, SNH said it was not convinced of the case for a change now.
Environment Minister Ross Finnie said such a move would be "premature" and should be left to next year, when the park undergoes its first five-year review.
Mr Swinney said: "I think a mistake was made four years ago because the very important area of the Highlands and East Perthshire was excluded from the park in the final decision.
"SNH consulted extensively about this issue and they took the view that it was topographically and environmentally significant."
The environment committee's convener, MSP Maureen Macmillan, said it had amassed a pile of written evidence on the bill, with a mixed reaction.
"Some people are very much in favour if it, other organisations a bit fearful of it," she said.
Reaction to extending the boundaries has been mixed
Blair Atholl businessman Geoff Crerar said some concerns had been expressed about planning restrictions in the town if the bill was passed, but added that it would bring a good foundation to the area.
"We're in a fragile economy and we need to make sure that we underpin everything that's here as much as we can," he said.
The bill has also received the backing of several lobbying groups.
Bill Wright of Parc, the Perthshire Alliance for the Real Cairngorms, said: "The requirements of the national park is that it is an area of coherent identity. Clearly it's not an area of coherent identity if you're splitting mountains in half."
Dave Morris, director of the Ramblers Association Scotland, added: "Above Blair Atholl is some of the most remote land in the United Kingdom and it is essential that it is all contained within the park."