Locals in shock after Nimbin 'inferno'

An "inferno" that destroyed the main street of the northern NSW hippy town of Nimbin and a number of its best known landmarks is believed to be suspicious, police say.

Residents say about eight businesses including the Nimbin Museum, the Rainbow Cafe and the Bring a Bong Cafe went up in flames.

At least two timber buildings built in the 1920s and a number of neighbouring buildings were also gutted.

There were no injuries, the Rural Fire & Service (RFS) says.

Locals were in shock as they woke to the news of the fire, which raced through Cullen Street in the early hours of Wednesday.

Darren Butcher, who runs the Nimbin Bakery, had just started work when he was forced to evacuate the building.

"There's about eight businesses that have been completely destroyed," he told AAP on Wednesday.

"It's sad for the town - (we're) in shock and disbelief."

Museum manager Michael Balderstone says the fire will have a huge impact on the town, known for its alternative culture and has a population of about 1000.

"It's really right in the middle of town, the Rainbow's probably the heart," he told ABC Local Radio on Wednesday.

"The museum's the biggest tourist attraction. It's a bloody mess."

Partner in the Nimbin Museum, Elspeth Jones, says she got a phone call about the fire at 4am.

"We drove straight here, but 10 kilometres out I could see the glow in the sky and I knew it was bad," she told the Northern Star newspaper.

"It was an inferno.

"It's just old wood, but it's also Nimbin's history.

"I've been coming to this museum every day for 22 years. It's been in my constant care.

"I am in shock."

Nimbin survives on small businesses, and there's already a lot of unemployment, Mr Butcher said.

"But we're very resilient out here," he said.

Emergency services, including nine fire engines, were called to the blaze just after 3am.

It has been put out and a crime scene has been established with specialist forensic investigators at the site.

One local tweeted "So much of Nimbin in gone forever".