The park is closed, and all permits for special events in October have been rescinded, a park statement said.
That includes two planned weddings and "First Amendment" demonstration of the white supremacist Confederate White Knights of the Ku Klux Klan, which received a permit to congregate near Meade's Headquarters on the Gettysburg battlefield grounds during the upcoming weekend, the news website Pennlive.com reported Tuesday.
The Ku Klux Klan is among a growing list of radical anti-government groups, the Southern Poverty Law center reported earlier this year.
Richard Preston, head of the Maryland-based Klan group, said he has people looking into the possibility of holding the rally in Gettysburg's town square, adding he will likely attend a rally Saturday with no more than 10 participants.
He did not mention the number of people expected at the battlefield demonstration.