We'll update this story as parks modify their operations. For the complete, current list, check out the National Park Service's news releases.
Update, April 6: Isle Royale, Bryce Canyon
Not exactly a closure, but Isle Royale will delay its opening date due to the ongoing COVID-19 pandemic. The park's islands are tentatively slated to open on June 15. Unlike closures at Zion, Grand Canyon, or Rocky Mountain, the postponement is unlikely to affect too many tourists' plans: With under 26,000 visitors in 2018, Isle Royale is the least-visited national park outside of Alaska.
Also closed as of Monday is Bryce Canyon National Park. In a press release, the park service said Superintendent Linda Mazzu, with the support of the Secretary of the Interior and the acting director of the National Park Servce, had made the decision to close the park after receiving a letter from the Southwest Utah Public Health Department.
Update, April 5: Death Valley, Zion
Two western desert parks closed to visitors over the weekend. Zion National Park in Utah, the most-visited park still operating, officially shut on Friday, April 3, following a request from Utah's state health department. Zion had already closed the popular Angels Landing Trail, but widely-circulated photos showed crowds still gathering in the park.
On Saturday, April 4, Death Valley National Park announced that it would close until further notice as well.
Update, April 3: Big Bend, North Cascades, Dry Tortugas, Congaree
Four more parks have joined the list of closures. On April 2, Congaree National Park in South Carolina and North Cascades National Park in Washington fully closed to visitors. Florida's Dry Tortugas National Park closed all islands in the park; it will continue allowing boats in its waters.
On April 3, Texas's Big Bend National Park announced it would also shut to all visitors until further notice, as would the Rio Grande Wild and Scenic River.
In addition to the parks, the Buffalo National River closed to visitors on April 2. Find the most current list of closures on the National Park Service's site.
Update, April 1: Grand Canyon
Grand Canyon National Park will close to all visitors effective immediately, the National Park Service said on Wednesday afternoon.
The National Park Service said on Tuesday that it had not received any request to close the park from local health authorities; however, in a letter sent March 27, Coconino County's top health officer and the chair of its board of supervisors expressed "extreme concern" for the agency's decision to keep the unit open. In a statement on Wednesday afternoon, Interior Secretary David Bernhardt seemed to say that the department had just seen the letter.
"The Department of the Interior and the National Park Service will continue to follow the guidance of state and local health officials in making determinations about our operations," Interior Secretary David Bernhardt said in a statement. "As soon as we received the letter from the Health and Human Services Director and Chief Health Officer for Coconino County recommending the closure of Grand Canyon National Park, we closed the park."
Update, March 31: Joshua Tree
Joshua Tree National Park will fully close to visitors starting on Wednesday. A news release from the National Park Service said the agency had made the decision in consultation with the San Bernardino County Public Health Office. The park was already operating under significant restrictions, having banned motor vehicles a week prior.
Update, March 30: Appalachian Trail
The National Park Service is closing all Appalachian Trail shelters and bathrooms on lands under the administration of the Appalachian National Scenic Trail Park Office, the agency announced on Monday. The closures affect 56 shelters and 75 privies; the statement goes on to note that there is no legal place to spend the night along the Appalachian Trail in either Maryland or Massachusetts, and that all shelters in New Jersey are closed under a state order as well. The move comes nearly two weeks after the Appalachian Trail Conservancy asked aspiring thru-hikers to cancel or postpone their trips due to the risk of contracting or spreading coronavirus.
Update, March 28: Canyonlands, Arches, Glacier
Arches and Canyonlands National Parks will close to all visitors beginning on Saturday, following requests from the Southeast Utah Health Department, San Juan Public Health, and Moab Regional Hospital. The hospital, which has just 17 beds, had previously urged Utah Governor Gary Herbert to take action to close Arches, warning him that a surge in cases could quickly overwhelm its facilities.
On Friday, Grand County, which contains Moab, Arches, and part of Canyonlands, announced that it had confirmed its first coronavirus case. Neighboring San Juan County, the home of Bears Ears National Monument and another part of Canyonlands, reported its first case as well. A public health order on Friday temporarily banned non-residents from camping ins the county.
Also shuttering: Glacier National Park, which closed to visitors at 5 pm Friday.
Update, March 27: Mesa Verde, Devils Tower
Mesa Verde and Congaree National Parks are among the latest National Park Service units to close. Devils Tower National Monument in Wyoming and Pipe Spring National Monument in Arizona have shut their gates as well.
In addition to the full closures, Grand Canyon National Park has put additional restrictions in place, banning hikers from the Bright Angel, South Kaibab and North Kaibab trails and suspending permits for the Bright Angel, Indian Garden, and Cottonwood campgrounds.
Find the full list and latest information about closures on the National Park Service's site.
Update, March 24: Yellowstone, Grand Teton
Yellowstone and Grand Teton National Parks are among the latest National Park Service units to close due to the ongoing coronavirus pandemic. In a statement, the National Park Service said it was closing the parks to all public access at the request of health officials from four local counties in Montana and Wyoming.
Also closed today is Great Smoky Mountains National Park; all areas of the park are cutting off public access except for the Foothills Parkway and the Spur. In Oregon, Crater Lake National park fully closed to visitors on Tuesday.
Other parks have extensively modified operations, but have not fully closed: Joshua Tree National Park is closed to motor vehicles, while Mount Rainier has banned both cars and bicycles from its roads. Zion National Park closed popular areas, including part of the Angels Landing Trail. In Washington, Olympic National Park put a laundry list of changes in place, including closing the park to all overnight camping including in wilderness areas.
Original Post: Yosemite, Rocky Mountain
Yosemite National Park and Rocky Mountain National Park announced on Friday that they would both close to the public immediately, becoming two of the most high-profile spaces in the outdoors to shut down because of COVID-19
In a press release, the National Park Service said it was shutting down Rocky Mountain National Park at 7 pm MDT at the request of local health officials; Yosemite shut down at 3 pm PDT. Both closures will run 24 hours a day, 7 days a week until further notice, the agency said.
Prior to the closures, local health departments and elected officials had urged the Interior Department to shut down both parks. On Friday, Mayor Todd Jirsa of Estes Park, the main gateway to Rocky Mountain, urged Secretary of the Interior David Bernhardt to close access to the park.
In a letter to the Secretary, Jirsa said that "a continued influx of visitors at this critical time presents a grave public health concern to Estes Park and our surrounding communities."
"Medical and emergency services, as well as basic supplies like groceries, must be available to meet the needs of our community at this time," Jirsa wrote. "Estes Park is not in a position to support the potential needs of extra guests at this time."
Dr. Eric Sergienko is the public health officer for Mariposa County, which contains part of Yosemite National Park. In an interview with the San Jose Mercury News, Sergienko said that he had sent a letter to Yosemite's Acting Superintendent Cecily Muldoon recommending that she shut down the park.
While visitors are barred from the park, employees, contractors, and residents of communities within the park's boundaries will still be allowed inside.
More than fifty parks, monuments, and historic sites administered by the National Park Service have announced partial or complete closures in the last two days. Hawaii's Haleakala National Park announced its own shutdown yesterday, while Everglades National Park, Grand Canyon National Park, Carlsbad Caverns National Park, and other units closed visitor centers and cut services.