How does the US federal government shutdown affect you? Not every federally funded agency, program and service will grind to a halt -- just those considered nonessential.
So if you had plans to visit any national parks, monuments or museums, some will be closed.
Here's a look at how they might be impacted:
Interior Secretary Ryan Zinke said Sunday tourist spots should not "be weaponized" and he has decided to keep many national parks open.
Zinke's decision to leave open as many park gates as possible means about two-thirds of the 417 national parks are still open to the public, according to the National Parks Conservation Association, an advocacy group.
Open-air parks, with their hiking trails and sprawling scenery, will largely remain open but will have limited services as about 21,000 of the park service's 24,000 staff members will be furloughed. Law enforcement personnel considered essential will be working, but rangers, gift shop and restroom staff will not, for example.
Yellowstone National Park said the park was still accessible but government-run operations and facilities are closed. "Visitors can also access commercial services in the interior of the park (e.g. at Old Faithful) only as long as concessioners provide funds for road grooming," it said on its website.
Rocky Mountain National Park said it was still accessible but with limited services and visitors would be entering at their own risk. "Park visitors are advised to use extreme caution if choosing to enter Rocky Mountain National Park, as National Park Service personnel will not be available to provide guidance or assistance. Emergency services will be limited," it said.
Everglades National Park, Biscayne National Park, Dry Tortugas National Park, and Big Cypress National Preserve are accessible with limited services.
Mount Rushmore National Memorial said NPS facilities were closed but concession facilities were operating, including parking, food and beverages and restrooms.
All of Boston's National Parks are shut, the Boston National Historical Park said on Twitter.
On its website, the Bureau of Land Management, also run by the Department of the Interior, said "the majority of BLM managed lands remain accessible to visitors; however access may change without notice." It said its website would not be updated and there would be no visitor services at its sites.
The US Fish and Wildlife Service, which has 566 refuges and 38 wetland management districts, said refuges requiring the presence of a federal employee or contractor would be closed.
The Rocky Mountain Arsenal NWR tweeted that First Creek Trail and perimeter trails would remain open, but it later said the majority of the refuge would be inaccessible due to an approaching storm and the inability to maintain roads and provide safe public access.
The National Park System also includes buildings such as Ford's Theater in Washington, where President Abraham Lincoln was assassinated, and Independence Hall and the Liberty Bell in Philadelphia. Those buildings will be closed.
"We welcome your visits and pray/advocate for an expedient, humane conclusion to the government shutdown," the center said.
The Oklahoma City National Memorial and Museum said it would continue to operate normally -- though no National Park rangers would be on site. "While the Memorial is an affiliated site of the National Park Service, it is privately owned and operated by the Oklahoma City National Memorial Foundation," it said.
The Manhattan Project tweeted: "Some @MnhtnProjectNPS areas may be accessible, however access may change without notice, and there are no NPS-provided services," it said.
NASA has closed off tours.
Open for business
New York Gov. Andrew Cuomo said in a statement Sunday that the Statue of Liberty and Ellis Island would reopen Monday.
The state is using its tourism budget to fully fund personnel and operational costs at $65,000 per day, Cuomo said.
"The Statue of Liberty is a symbol of freedom and opportunity for all, and it is a gross injustice that this administration's dysfunction caused it to shut down," he said. "New York State will not allow the vitriol of Washington to close the Statue of Liberty."
The Smithsonian said in a tweet that "its museums, research centers, and the National Zoo" will be open Monday.
"The Smithsonian can use prior year funds still available to us to do so. We will update our status beyond Monday as soon as we know," the tweet said.
President Lincoln's Cottage in Washington, D.C. tweeted that it would be open despite the shutdown.
It even offered federal employees a discount, saying: "Federal employees, all this week we're running a deal. Bring your federal ID/business card and tickets are $12.50 #GovShutdown."
Washington Mayor Muriel Bowser said Friday the city plans to help the federal government maintain the National Mall.
"I've called on my agencies, where we are able, to step in for the federal government," she said in a news conference.
"The National Mall is operated by the National Park Service, and there are many other National Park Service properties throughout Washington, D.C. ... we will step in and ensure litter and trash are picked up along the National Mall to keep the nation's front yard clean of debris."
Arlington National Cemetery also will remain open during the shutdown.