A blaze at an iconic Borscht Belt hotel Tuesday night is now under investigation.

The fire started at the “Winter Building” of the former Nevele Grand Hotel in the Town of Wawarsing around 9:30 p.m., according to Ulster County officials.

“The whole building was fully involved,” says Everett Erichsen, director of Ulster County Emergency Services.

The once-thriving resort on Arrowhead Road was built in 1901 and closed more than a century later, in 2019 - after the Catskills became less popular to vacationers from New York City.

So far, it’s not clear how the fire began.

“It’s unfortunate. We are going to be investigating,” Erichsen says.

The fire was captured in multiple images sent to News 12 by a viewer showing the building fully engulfed in smoke and flames.

The 463-acre property was most recently purchased by 1100 Arrow LLC in 2023, according to multiple media reports. Ulster County property records online list the property owner’s information as “not available” but show it was purchased for $5 million in 2023.

Plans were widely reported last year that the new owners and NYC-based developer, Somerset Partners, planned to demolish the property to build a new hotel, condos and cottages.

News 12’s efforts to find a working phone number for 1100 Arrow LLC were unsuccessful. An email was sent out to Somerset Partners for information.

The iconic destination resort is the fourth Borscht Belt hotel to catch fire after closing and falling into ruin. Pine Hotel in Fallsburg burned down last June and the Homowack Resort caught fire last July. The famous Grossinger's Resort Hotel in Liberty, which inspired the blockbuster film "Dirty Dancing" was destroyed in a fire in 2022.