A Darwin butcher has been awarded Best Gay Ute at the Adelaide River Music Muster south of Darwin, the first ute competition in Australia to feature the category.

Nikki Harriman's purple Holden, nicknamed Within Temptation, was the only entrant in the Gay Ute section and one of just three utes in the entire muster.

Ms Harriman traded in a Toyota Corolla to buy her first ute when she 19.

"When I was little I always used to drool over utes when they drove past me," she told the ABC last week as she prepared her ute for competition.

"I think they look sexier than most other cars."

The narrow field of three entering the ute muster competition at the Adelaide River Music Muster. ( ABC News: James Purtill )

Ms Harriman and Within Temptation had won Best Chick's Ute at several Territory musters before.

Traditional categories in an Australian ute muster include Best Street Ute, Country Ute, Chicks Ute and Feral Ute, with each category rewarding different features such as bull bars, aerials, engine size and decorations.

"Normally I'll start with the interior and I'll vacuum and polish and clean the interior - then I normally do a degrease and clean the engine bay," she said.

"It can take up to six hours just to polish my bull bar.

"A ute muster is the country version of a street car show or a sound off comp. You put your car in, you make it look pretty.

"You nominate what classes you want to go in and you dress your ute accordingly."

Mount Bundy station in the Northern Territory. ( ABC News: James Purtill )

The Adelaide River Music Muster at Mount Bundy station. ( ABC News: James Purtill )

The young and old gathered at the muster at the Mount Bundy station. ( ABC News: James Purtill )

'Boys worried what people will think of them'

Ms Harriman said "in certain circles" in the Northern Territory being openly gay was still "a big deal".

"Some of the old fashioned people don't agree with our choices in life, to put it nicely," she said.

In the lead up to the event, Ms Harriman had expected several other women would enter the Best Gay Ute section, but doubted any men would join them.

"Most of the boys won't go into it because they're worried about the repercussions of going into the section and what people will think or say to them," she said.

Ms Harriman said the inclusion of the new category was not provocative but necessary for the future popularity of Australian ute musters.

"I was a little bit concerned for them having it because there's never been one in Australia before," she said.

"The utes in Australia are slowly dying off. They used to be really, really big about 10 years ago. I think they're looking for new categories and entrants to pull more entrants into it."

Ute pull competition at the Adelaide River Music Muster at Mount Bundy station. ( ABC News: James Purtill )

Volunteers for the NT Aids and Hepatitis Council, which sponsored the Best Gay Ute competition of the Adelaide River Music Muster. ( ABC News: James Purtill )

'You wouldn't have seen this 12 years ago'

The NT Aids and Hepatitis Council (NTAHC) are sponsors of the Gay Ute competition and sent a crowd of cowboys in pink hats to the muster.

"You certainly wouldn't have seen this 12 or 15 years ago," the NTAHC's Daniel Alderman said.

Another pink hat wearer, Sian McLaughin, said although the NT can be rough, "it was also one of the most accepting places in Australia".

Reactions from the crowd were mixed.

"The longer we live the more we get adapted to these things, so we've got to learn to live with it I guess," one country music fan said.

But others were less prepared for change.

"They should keep it to themselves and not advertise it in the community. It's not natural," another added.

"Some of the old fashioned people don't agree with our choices in life, to put it nicely," says Nikki Harriman, with her partner Tarmara. ( ABC News: James Purtill )