WASHINGTON -- A Walmart is going up near the Virginia forest where Robert E. Lee and Ulysses Grant first faced off. Highway construction threatens the historic buildings of a Mississippi town that was spared by Union troops. The Gettysburg battlefield where Lincoln delivered his famous speech could be home to a Comfort Inn and Suites.

These are some of nation’s most endangered Civil War battlefields, according to the Civil War Preservation Trust’s annual report released Wednesday at the National Press Club.

The report identifies the trust’s the top 10 threatened Civil War sites in the U.S. and what can be done to save them.

“In town after town, the irreplaceable battlefields that define those communities are being marred forever,” said James Lightizer, president of the nonprofit. “As we approach the sesquicentennial of the bloodiest conflict in our nation’s history, we need to be more aware than ever of the importance of preserving these sacred places for generations to come.”

Academy Award-winning actor Richard Dreyfuss, an avid history student who has worked on Civil War documentaries, was at the unveiling to speak about the importance of battlefield preservation.

“These hallowed battlegrounds should be national shrines, monuments to American valor, determination and courage. Once these irreplaceable treasures are gone, they’re gone forever,” said Dreyfuss, best known for his roles in the movies Jaws and The Goodbye Girl.

Civil War Preservation Trust spokesman Jim Campi said the group is not looking to preserve every bullet shot or every piece of land a soldier fought on, just the sites that tell the story of the Civil War.The battlefields were chosen based on geographic location, military significance and the immediacy of current threats.

The battlefield in Wilderness, Va., is one of the most controversial preserved sites. A Walmart store is under construction adjacent to the preserved land. Campi said the heavy traffic that Walmart will bring will destroy the battlefield.

“Walmart can move a half a mile down the road and we will be fine,” said Campi.

Walmart officials were not immediately available for comment.

Port Gibson, Miss., is the only town on the trust’s endangered list. Local lore has it that Union forces marching through Mississippi spared the town of Port Gibson from the torch because it was too beautiful to burn—but now the widening of U.S. 61 through downtown threatens it wipeout.

“Preservation is about serious long-term commitment and if we widen that street we will lose that eternally,” Libby O’Connell, vice president of the History Channel, told the audience.

Gettysburg made the Top 10 list because of a Comfort Inn and Suites under construction on Cemetery Hill on the Gettysburg National Military Park.

“Gettysburg is the only sacred soil in the United States,” said Dreyfuss. “It is worth it to go there. When you are at Gettysburg you weep. You weep because it is American history.”