The doors remained locked at Fort McHenry National Monument in Maryland, the birthplace of the US national anthem. In Georgia, the Fort Pulaski National monument announced it would be closed except for one boat ramp. At Washington’s Mount Rainier national park, ranger-led snowshoe walks were cancelled.

And at the Rosie the Riveter/WWII Home Front National Historical Park in Richmond, California, a scheduled talk by the nation’s oldest park ranger, 97-year-old Betty Reid Soskin, had to be called off.

As the early hours of the federal shutdown dawned at national parks, seashores and monuments around the nation, it quickly became apparent that many travelers would have to cancel or seriously scale back their visits owing to the lack of park service staff.

Gates closed at @WilliamTaftNPS this morning, due to the government shutdown. This park site is the birthplace and childhood home of the 27th President of the United States. pic.twitter.com/ZEdiMJq9Dx — National Parks Conservation Association (@NPCA) December 22, 2018

At Yellowstone, Yosemite and many other major parks, the park service announced it would keep the access to parklands open, but many services, including restrooms, trash removal, some visitors centers and snow removal, would cease.

As a rule, it said, if a facility or area is locked outside of normal business hours, such as a parking lot, it would stay locked through the shutdown.

State governments in New York, Arizona and Utah, scrambled to provide local funding to ensure that key sites including the Statue of Liberty, the Grand Canyon and Zion national parks could remain open.

“Visitors from around the world who have planned their trips to our national parks months in advance now face the possibility of disruption and disappointment when they arrive at parks only to find closed visitor centers, locked restrooms and unplowed roads,” Theresa Pierno, the president of the National Parks Conservation Association (NPCA), said in a statement.

A ranger closes a road in Rocky Mountain national park, where spots remain unplowed. Photograph: David Zalubowski/AP

During the last shutdown, in January 2018, 21,000 park service employees were furloughed leaving just 3,298 “essential staff” to manage 80m acres of national park lands, according to the NPCA.

Some privately-run park partners and concessions operators are, by now, so used to dealing with federal shutdown threats that their plans to deal with them run like clockwork.

By the time the shutdown started at 12.01am Saturday, Alcatraz Cruises, the company that takes tourists through the historic federal penitentiary site at Alcatraz Island national park, had its government shutdown strategy fully in place.

An advisory notice telling customers what to expect was pre-programmed to pop up on the company website; a raft of apologetic emails was set to automatically go out to customers.

For the 3,500 tourists per day who had pre-booked regular day tours, the news was good: the private concessionaire will be able to continue to run its regular, daytime excursions to the infamous island jail. But another 650 people a day, who booked months ahead for special “behind the scenes” and night tours, will be out of luck and see their long-awaited trips cancelled.

“It’s the worst possible time,” said Antonette Sespene, the director of sales and marketing for the Alcatraz Cruises, which is the national park’s Alcatraz contractor. “We’ve been sold out through the Christmas holidays for the last six to eight weeks. There isn’t another boat we can put these people on.”

Special tours on San Francisco’s famous Alcatraz Island have been cancelled. Photograph: Justin Sullivan/Getty Images

“Unfortunately, we’re getting really familiar with this situation, which I wish wasn’t the case,” she said. “There are going to be so many disappointed people”

Seth Zaharias co-owner of the Cliffhanger Guides, which offers climbing tours in Joshua Tree National Park, headed out with a tour group for what he hoped would be an normal day of rock climbing in the park, but he worried about the effects of a prolonged shutdown.

“I don’t think the real impacts will come this weekend; they will really hit if this thing drags on,” he said. “It’s going to come down to environmental degradation. It’s going to be trash; it’s going to be human waste; it’s going to be people driving around on the land.”

“We expect to have about 100,000 people out there in the park during the holiday season, so if .1 percent do stupid things, that could have a big impact.”

The Hawai‘i Volcanoes National Park announced many areas would remain open, but campgrounds would be closed and entrance fees would not be charged. Other federal recreation areas, including Florida’s Everglades National Park, Maryland’s Assateague Island National Seashore and Utah’s Dinosaur National Monument said they would remain accessible to visitors although they would offer virtually no services.

Haley Woods operations director of Southern Yosemite Mountain Guides said she expects Yosemite will still offer a beautiful winter retreat. But she is not sure if there will be enough snow clearing staff to keep roads open if it snows.

“It definitely does create uncertainty,” she said. “It makes people wary of coming at all. It’s hard to tell people what to expect.”