Demonstrators showed up at national parks across the country Saturday to protest the firing of thousands of park workers.

It’s the latest protest by park advocates against the massive federal layoffs instituted by President Donald Trump and Elon Musk, who continues to orchestrate the firings without an official position in the government. While Trump and Musk have now fired tens of thousands of workers across many federal agencies, the blow to the nation’s park system has been especially galling, according to protesters and park advocates.

After a “Valentine’s Day massacre” last month that resulted in about 4,500 park workers losing their jobs, many conservation groups have sounded the alarm about the danger to the country’s parks. Also, some former park officials have suggested that Americans change their summer plans to avoid stressing an understaffed park system during the busy summer months.

The tensions led to the protests this Saturday, organized by Resistance Rangers. Roughly 700 off-duty park rangers formed the group, including some recently fired from the National Park Service. Nearly 12,000 people joined protests across more than 170 parks on Saturday, according to Resistance Rangers. Several parks, including Rocky Mountain, Mt. Rainier, Yellowstone, and Yosemite, saw hundreds of protestors.

“The protests yesterday were huge, but they’re just the tip of the iceberg,” outdoor photographer and influencer Madeleine Wilson said. “We are just getting started.”

Defending ‘America’s Best Idea’

The protests against Trump’s layoffs took many forms. At Rocky Mountain and Zion National Parks, protestors lined the road leading to the park entrances. Many carried signs with messages like “Our Parks Aren’t For Sale” or “Hug A Bear, Elon.” At other parks like Yosemite, the rallies happened inside the park. Some protest leaders gave speeches and led chants demanding the reinstating of fired park rangers.

Many protests used an upside-down American flag to represent their frustration with Trump’s policies and defend the national parks, which have often been called “America’s Best Idea.” The inverted flag appeared at highly visible locations in many national parks this weekend. It was attached to El Capitan over the weekend, as well as large rock walls at Joshua Tree, Arches, and Rocky Mountain National Parks.

Videos from the Resistance Rangers account showed large protests at many other national parks. That includes Yellowstone, Bryce Canyon, Saguaro, Great Smoky Mountains, Mammoth Cave, Indiana Dunes, Olympic, Shenandoah, and Cuyahoga Valley.

Protesters continue to create new methods to show their displeasure. That includes putting up signs in front of parks’ live webcams, SF Gate reported. A sign in front of the webcam at the Badger Pass Ski Area at Yosemite says, “Go Badger Your Reps.” It also includes the phone number for the office of Congressman Tom McClintock, who represents the area.

However, without sufficient staff at America’s national parks this summer, those intending to visit the parks should expect reduced services. That’s according to the National Parks Conservation Association, which also advised caution over reducing safety for visitors.

“These staffing cuts will put a major strain on an already understaffed and overwhelmed Park Service,” the group said in a statement. “Weakening the National Park System risks irreversible damage to America’s greatest legacy. Parks are supposed to be where people can experience the best of America, but these cuts put all of that at risk.”