Southland district Mayor Frana Cardno wants as many people as possible to oppose a plan to build a tunnel through Fiordland National Park.
The Department of Conservation is calling for public submissions on the plan, by Milford Dart Ltd, to construct a 10km tunnel linking Queenstown with Milford Sound.
DoC is allowing 40 days for submissions before it approves the project.
Ms Cardno says building a tunnel would be lunacy as it would destroy parts of the park.
She says it would also draw tourists away from Te Anau, meaning tourists would spend less time in New Zealand.
But Milford Dart managing director Tom Elworthy says the tunnel will means tourists spend less time on a bus and more quality time sightseeing.