A footbridge used by hundreds of thousands of hikers each year to cross the Potomac River in Harpers Ferry, W.Va., is closed indefinitely, National Park Service officials said.

The pedestrian path was damaged two months ago when a CSX freight train derailed on the tracks next to it.

The derailment sent two rail cars into the Potomac River, wiping out a section of the Civil War-era bridge. Officials have offered no specific information about what caused the seven-car train to derail. No one was injured.

The train line was restored a day after the Dec. 21 derailment, but the National Park Service said it is still assessing the damage to the footbridge. NPS is coordinating the restoration efforts with CSX, which will cover the cost for the repairs.

“The National Park Service is working to understand the full extent of the damage to the footbridge and options to repair it,” said Autumn Cook, a spokeswoman for Harpers Ferry National Historical Park.

The footbridge closure affects hundreds of thousands of visitors, including hikers traveling from across the East Coast. Nearly 300,000 people visited Harpers Ferry National Historical Park last year, officials said.

The bridge is a key piece of the 2,190-mile Appalachian National Scenic Trail that stretches from Georgia to Maine. It also draws scores of visitors who cross the Potomac to get to the Maryland Heights overlook, a spot on the Maryland side that offers spectacular views of Harpers Ferry and the water. The bridge connects to the C&O canal towpath, the 185-mile trail between Georgetown in the District and Cumberland, Md.

The closure has created problems for hikers who have had to rely on private shuttle services to get across, according to users and trail volunteers. But the disruption is expected to worsen as the weather gets warmer and the number of hikers and tourists grows. With no other good walking alternative to get from one end of the bridge to the other, trail advocates fear that hikers may turn to heavily trafficked U.S. Route 340, which has narrow shoulders and no pedestrian facilities.

“It won’t be safe to have hundreds of people walking in that road,” said Jim Fetig, a volunteer with the Potomac Appalachian Trail Club and an avid hiker from Kensington, Md. “It will be very risky for people to be walking on Highway 340.”

The National Park Service and CSX are planning to provide a shuttle service that would transport hikers and visitors around the footbridge closure until repairs can be completed, agency and company officials said.

“The time-frame for the bridge to reopen remains uncertain,” Cook said, adding that NPS is discussing options for repairs and assessing the rebuilding of the footbridge. “We understand that access to the footbridge is important to hikers and visitors to the area, and are working to reduce the inconvenience.”

CSX said in a statement that it is working with the National Park Service and is committed to covering the cost of the bridge reconstruction.

“CSX shares the community’s desire to restore the walkway bridge and limit further disruption,” the company said.

Some trail and tourism groups have been urging the agency to move quickly on restoring the crossing.

“It is a real detriment not having it and a real inconvenience for hikers who are trying to make their way through,” said Jordan Bowman, a spokesman for the Appalachian Trail Conservancy, which maintains the trail.

“What we would love is for the bridge to be fixed as soon as possible, and until that happens we need to have some other sort of transportation set up,” Bowman said. “Ideally a shuttle service should be in place to take care of that.”

Without the bridge, the hiking experience isn’t the same, Fetig said.

“You want to keep the experience as pure as possible and riding on shuttle buses and skipping miles is not the way that we like to do it,” Fetig said. “I would hope that the bridge could be repaired and be ready in time for when the majority of the hikers come through.”