The entrance to the Historic Western & Atlantic Railroad Tunnel was operational from 1850 until 1928. It sat neglected until 1992 when restoration efforts began, and was opened to the public in 2000.

In 1862, Union saboteurs known as Andrews' Raiders drove The General, the locomotive they hijacked, through Tunnel Hill, Ga., as pursuing Confederate forces closed in during The Great Locomotive Chase.

Since January, visitors have been traveling the 1,477-foot-long train tunnel in comfort on an eight-passenger golf cart while tour guides share the tunnel's history. The $9,000 cart was half paid for by a state tourism grant and half locally funded.

Being able to give tourists an alternative to walking the tunnel's length is one reason the number of visitors has tripled at Tunnel Hill from about 1,900 people annually two years ago to more than 6,000 now, said Ty Snyder, manager of the visitor center there.

"We've already passed 6,000 this year. It's a big increase," Snyder said.

Sue Orben, of Kissimmee, Fla., who was visiting Friday, marveled that the men digging the tunnel in the mid-1800s met in the middle and were only one-sixteenth of an inch off.

"They didn't have the technologies that we have today to figure out -- are we going in the right angle to get there? ... But, at that period of time, the knowledge that we had without the technology was amazing," she said.

Officials in Whitfield County are working to raise Tunnel Hill's profile and attract more visitors to the Western & Atlantic Railroad passage. The tunnel opened in 1850 after Irish railway workers spent two years hewing it by hand through the base of Chetoogeta Mountain.

"We've got a five-year plan for that area," said Brett Huske, executive director of the Dalton Area Convention and Visitors Bureau.

The plan includes the following:

• Improved signs: Tunnel Hill is advertised on a new billboard at the Cloud Springs Road exit on southbound Interstate 75.

Soon, the Georgia Department of Transportation is due to install official brown historical marker signs on exit 341 of Interstate 75.

Tunnel Hill became eligible for the state signs when it passed the 5,000 annual visitor threshold, Snyder said.

"I think it'll make it easier to find," Snyder said.

Additional new signs put up in 2011 lead visitors from the interstate to the tunnel.

• Name change: "One of the biggest things we did is change the name of the site," Snyder said.

The name had been Tunnel Hill Heritage Center. Snyder said the problem with that was visitors "didn't really understand we had a tunnel here."

The official new name is the Historic Western & Atlantic Railroad Tunnel.

• Increased staffing: "We've doubled the [afternoon] staff out there," Huske said.

Previously, Tunnel Hill only had one person working at a time, and the visitor center would be unstaffed when that employee was leading tours. Now there's another employee working from noon to 4 p.m. -- the busiest time of day.

"That allows us to increase our capacity and improve our visitor experience," Snyder said.

• Clisby Austin House: Built in 1848, this house served as headquarters for Union Gen. William T. Sherman during the Battle of Dalton.

"Sherman holed up for six days planning the Atlanta campaign," Huske said.

Until the spring of 2011 the brick antebellum house was a private residence. Now it's part of Tunnel Hill. It's open periodically to visitors and next year could open daily, Snyder said.

• Train depot: The next step for the site, Huske said, is to fix up and reopen the train depot that was built in 1850 with stone excavated from the tunnel.

"Right now, it's not safe to let anybody in there," he said.

Officials are hoping to get a state grant to figure out how much restoring the depot would cost.

Improvements at the Western & Atlantic Railroad Tunnel are a joint effort among Tunnel Hill, Whitfield County, the Dalton Area Convention and Visitors Bureau and the Tunnel Hill Historical Foundation.

Officials say work is paying off at the historic train tunnel that opened to the public in 2000.

"It's becoming more and more self-sufficient," Snyder said. "It's generating enough to help pay for operating it."