GREEN’S GRANT — Fifty years after the last Glen House hosted overnight guests, the family-owned company that has operated the Mount Washington Auto Road since 1901 hopes to have the fifth iteration of the hotel open in May 2017.

On Monday evening, the Coos County Planning Board met at the Medallion Opera House in Gorham and granted conditional site plan approval to the Mount Washington Summit Road Company for a 65-room, three-story hotel on the grounds of the former Great Glen Trails Ski Lodge.

The lodge was located at the base of the auto road, slightly north of and across from the Base Lodge on Route 16, and it, like the last Glen House in 1967, met its demise by fire.

But robust fire detection and suppression — “as is the code these days,” pointed out Howie Wemyss, the auto road’s long-time general manger on Tuesday — will hopefully mean that the new Glen House will have a long, safe and successful history of caring for visitors to the oldest man-made attraction in America.

Weather permitting, Wemyss thinks construction of the hotel could begin in May and be completed in time for Memorial Day in 2017.

He added that while the auto road’s management knows how to operate it, “We are smart enough to know that we don’t know anything about running a hotel,” which is why discussions are currently ongoing with a company to run the hotel year-round.

The four families that make up the auto road’s ownership group will privately raise the estimated $11 million needed for construction, said Wemyss, and will likely hold majority ownership rights, too.

Following an up to three-year “stabilization” period, Wemyss expects the Glen House to have an average occupancy in the high 60 percent range and to employ about 30 people.

“We have felt since the loss of the last Glen House, which was ages ago in 1967, that there’s a bed need here on this property,” explained Wemyss.

This version of the Glen House, he continued, would bring “a level of lodging not currently available” in the immediate area around the auto road.

“It’s going to be very nice,” Wemyss promised, with most of the hotel’s rooms having balconies and offering a “resort mix” of options for the number of beds and configuration of rooms. The hotel would have an indoor pool and a meeting room, but not banquet facilities.

The hotel would be heated and cooled by a geo-thermal system, with Wemyss noting that two offsite energy-generating projects, one existing, one in the works — harnessing hydro and solar power — could in the near future make the hotel nearly energy sufficient and “carbon neutral,” too.