Nemo businessman Dan Martin could do nothing Thursday night but watch as three years of work went up in smoke.

His store, the Nemo Mercantile, was destroyed in a fire that began sometime Thursday night. By Friday morning, nothing was left of the 100-year-old building but rubble.

The blaze was reported about 8:40 p.m. Thursday, but by then, the building was badly damaged, according to Lisa Balistreri, a waitress at Nemo Guest Ranch across the road.

Nemo and Brownsville volunteer fire departments responded. Nobody was hurt in the blaze.

Martin has spent a number of years in Nemo, the historic logging and resort town 16 miles northwest of Rapid City. He ran the cafe and bar at Nemo Guest Ranch from 1968 to 1976, when his parents operated that business.

Three years ago, Martin began refurbishing the old building across the road from the the guest ranch. It was once a mechanic's shop. In the summer of 2005, he opened Nemo Mercantile.

The convenience store also sold groceries and camping supplies. He later added gas pumps and other services.

Martin was adding a new restaurant and bar to Nemo Mercantile, and the restaurant project was nearly completed when the fire broke out.

"It's kind of a shame; you work on something for three years, and you'd like to at least see it all it finished," he said Friday. "We were actually setting furniture and stuff in the restaurant this last couple of days."

He still had plumbing, kitchen work and a few other details to complete before opening. "We were getting real close," he said. Martin planned to open the bar and restaurant in early February.

He said the fire started somewhere around the fireplace. He had the fireplace built a year ago, and it was surrounded by concrete. "It seems strange to me, but who knows?"

Martin said he has asked the fire department to bring in investigators to look into the cause of the fire.

Once the building became fully engulfed by flames, Martin said, there was little firefighters could do. Beneath the building's tin roof were rough-sawn wooden rafters and planking milled at the old Nemo sawmill, he said.

"There's a lot of wood up in there, and once that caught on fire, it just didn't matter," he said.

Martin said Friday he doesn't know whether he will rebuild. "I don't if I've got the ambition to start over and work for another three years," he said, "And that was a pretty special old building. … I don't know what I'm going to do."