Happy birthday, Yosemite National Park.  

It's been an American and Californian treasure for 123 years. Ansel Adams loved Yosemite. So did John Muir and Teddy Roosevelt.

Heck, Google made a Doodle to celebrate.

Today, however, Yosemite will be celebrating alone.  Due to the U.S. government shutdown, the National Park Service, which runs all national parks and monuments, has ordered the park closed and is in the process of furloughing nearly all of its employees.

That includes Yosemite. Park rangers began notifying overnight guests and campers within the park early Tuesday that they will have 48 hours to vacate the park lands. All "day visitors," according to the Christian Science Monitor, will be asked to leave the park immediately.  

The process, known as the "National Park Service Contingency Plan," outlines how Yosemite and other national parks and monuments will be closed. The plan also indicates that emergency personnel, fire officials, and "essential" personnel will not take part in the employee furloughs that other federal employees are required to take.

Reach Executive Producer Colin Hale here. Follow him on Twitter.