A fire has destroyed the Wonderland Hotel Annex in Great Smoky Mountains National Park/NPS

Editor's note: This updates the story to note that an investigation into the cause of the fire is under way, and that two of the 19 structures remaining in the historic district have been restored, but funding is lacking to restore the remaining 17.

An investigation is under way to learn how a fire started in the Wonderland Hotel Annex at Great Smoky Mountains National Park and quickly engulfed, and destroyed, the slice of Appalachian history.

Park staff received a call a little after 7 a.m. Tuesday that the two-story structre was on fire, and by the time firefighters reached the site shortly thereafter the 8,600-square-foot building had been engulfed.

"The fire did not begin by natural causes, there was no sign of lightning strikes and there was no electricity within the structure," park spokeswoman Dana Soehn wrote in an email Wednesday. "We do not know when the fire started and have no suspects at this time."

The Annex had been scheduled for demolition. It was part of a complex of buildings that predated established of the national park. According to park records, the Annex, the Wonderland Hotel, and 74 cottages and outbuildings were located in the Elkmont section of the park and were purchased by the National Park Service when the lands were acquired to create Great Smoky Mountains.

The Wonderland Hotel Annex was a two-story frame building that set approximately 10 yards from the main hotel structure. The building contained 24 guest rooms, a common area, and a screened porch. In December 2006, the structurally-failed Wonderland Hotel was removed after a selection of historic materials was salvaged for conservation in the park’s museum collection. The annex structure was slated for removal pending available funding.

The Wonderland Hotel Annex, pictured here in 2001, was slated for demolition/NPS

A release from the park Wednesday morning said the "fire was contained to the immediate area of the structure covering approximately 0.5 acre. The area is bounded by gravel roads and a dense alluvial forest of hemlock and rhododendron which slowed the spread of the fire. Park crews will continue to monitor hot spots and burning snags over the next several days. The area surrounding the Wonderland Hotel site is closed to the public. Elkmont Campground and all trails in the area remain open."

The Elkmont Historic District was placed on the National Register of Historic Places in 1994. Upon its registration as a Historic District, 49 of the structures were noted as being of significance to the District. "Following a planning process in 2008, a Memoranda of Agreement was executed by the National Park Service, State Historic Preservation Office, and the National Advisory Councils for Historic Preservation that calls for the preservation of 19 structures and the removal of the remaining structures, including the Annex, as funding becomes available," the park release said.

Under that preservation plan, the 19 buildings, including the Appalachian Clubhouse, were to be restored and made available for public visitation, but no overnight stays. To date, the Appalachian Clubhouse and the Spence Cabin have been restored and are available for day use.