Carried in 165 often ancient vehicles, six of them irreparably lost on the way, the small army stopped in Glen Innes on Tuesday night after a long drive from Lightning Ridge.

Box Rallies founder James Freeman had the arguably bizarre idea after he lost both his parents to cancer in a twelve month period.

"Ninety per cent of the people here have a very similar story to me," he said.

"The rallies give them an outlet to be able to fundraise in a way in which they want to."

After ten years on the road, the 2019 mystery box crew had broken the record, raising over a million dollars in eight months of tough yakka.

Mr Freeman said through 2019 they will raise at least $5 million all told.

"Because of that we are the largest fundraiser for the Cancer Council in the country," he said.

"And we now are the second largest contributor to cancer research programs after the government.

"And it's because of these people."

Glen Innes Red Cross were on scene to make both dinner and lunch at the historic heritage-listed Showgrounds on Tuesday night as the drivers arrived.

Dozens of volunteers slaved away for the occasion.

Drivers learn of the day's destination the morning of a drive, though they know the rally will start and finish in Byron Bay.

One organiser told the Examiner she had to find a way of strongly recommending drivers pack for cold weather without giving the route away.

They camped out in the Showgrounds on a night which hit a low of 0.7 degrees.

Many of the quarter-century-old cars do not make the whole trip across "the roads less traveled", Mr Freeman said. They have lost six vehicles completely written off and sent to the great car yard in the sky, but a large proportion have had mechanical problems of some sort.

He pointed to the six cars in his team. Four had been knocked out.

"And that's normal.

"They break down; we fix them and press on.

"Some of them that we can't fix on the side of the road, then we'll wait for one of my support teams."

It's only if they can't be fixed in camp that they're written off.

"These rallies - yes they're fun, but they're a challenge.

"We're in the car all day and the roads that we travel on are rough, they're really rough."

The rally is a reward for fundraising and each participant is set a minimum of $3,500 raised, all of which is sent directly to the Cancer Council.

He said they had drivers from every state and territory, as well as California, New Zealand, England, Florida, and more.