The free return bus service, which attracted over 170 patrons last weekend, is a sweetener to encourage visitors back to the Grampians National Park after the recent bushfire threat.

The business group's vice-chair Jeff Lovell said Boroka Lookout, one of the Grampians' most accessible scenic lookouts, had been closed for rehabilitation following the fire.

"It's a pretty big blow for tourists not to have access to Boroka Lookout right now," he said.

"And the less scenic tourists we have in the area, the more economic impact it has on Halls Gap traders."

Mr Lovell said Halls Gap Tourism came up with the unique concept to offer a free bus ride from the Mt William car park to the mountain's summit as an alternative to Boroka Lookout.

"This is the first time that the public has been given access via vehicle to the stunning Mt William summit - the Grampians' highest point," he said.

"We really appreciate that Parks Victoria is giving us unprecedented access at least until Boroka opens again."

Mr Lovell explained that normally the two kilometre walk from the car park takes around 45 minutes and requires a good degree of fitness.

"The bus service opens up this part of the park for a whole new audience to enjoy; people with restricted mobility, the elderly or those with small children.

"Everyone has just loved it. We're really thrilled that we can capture this audience and encourage them to enjoy our park and visit Halls Gap."

Halls Gap Tourism has applied for state and federal government funding to reimburse the bus service operation fee.

The free bus runs daily from 10am to 2pm except for total fire ban days.

Please contact the Halls Gap Visitor Information Centre for further information on 1800 065 599.