Some of the country's most popular tourist sites might be closed temporarily if a war with Iraq raises new terrorist concern.
The Statue of Liberty, the Washington Monument, the White House, the St. Louis Gateway Arch and the Liberty Bell pavilion in Philadelphia would probably be temporarily sealed off, Interior Department officials said Thursday.
All five of those plus the road atop Hoover Dam in Nevada were closed to the public within days of the Sept. 11, 2001, terror attacks.
All but the White House, Statue of Liberty and the Hoover Dam road were reopened within a week, but only after new airport-type security measures such as metal detectors, bag searches, hand wands and sniffing dogs were added.
"The National Park Service is prepared to take the appropriate action, as we have in the past, to protect public safety and preserve these monuments and memorials," spokesman Dave Barna said.
More prominent dams -- such as the Grand Coulee in Washington state and Shasta in California -- also might be restricted from public access or closed if the terrorism threat increases, said Kip White, a spokesman for the Interior Department's Bureau of Reclamation.
Just last week the bureau, which manages 457 dams and 348 reservoirs, closed a road across the top of the Folsom Dam east of Sacramento, Calif.
The Interior Department has been developing emergency plans over the past five years, first for the millennium and then for homeland security after terrorists crashed commercial airliners into the World Trade Center and the Pentagon. Also on the government's priority list for protection is Mount Rushmore in South Dakota.
The Park Service already has increased patrols and guards at 11 more of the 388 areas it manages, primarily those that share borders with Canada or Mexico, or at seashores.
Other campgrounds or seashores also might have to be restricted or closed if rangers are called to other duties in case of an extreme national security threat. But officials said they will do everything they can to keep the parks open.
"The parks are a place for a renewal of the spirit and that's why it's especially important for them to be open during times of national crisis," Barna said. "We'll fight hard to see that they remain open."