Last month we celebrated the 100th Anniversary of our National Park Service. Historian Wallace Stegner once called our national parks “the best idea we ever had,” and I could not agree more.

My first job in the early 1970s was as a Park Ranger at the Lincoln Memorial on the National Mall in Washington, D.C. As a recent college graduate, I had the rare opportunity to share my love for one of our nation’s most cherished sites with visitors from the community and around the world.

The National Parks Service now manages 413 sites covering more than 84 million acres located in every state and territory. These areas include national parks, monuments, battlefields, military parks, historical parks, historic sites, lakeshores, seashores, recreation areas, scenic rivers and trails, and even the White House grounds. Many are easily accessible to us here in Northern Virginia.

As many presidents have before him, President Obama has built upon the legacy first established under President Grant and then grown by President Roosevelt, John Muir, and others. In honor of the NPS centennial, President Obama designated 87,500 acres in Maine as the Katahdin Woods and Waters National Monument, “the first national monument to preserve the landscape and honor the history and culture of Maine’s North Woods.” He will leave office this winter having protected more than 265 million acres of our public lands and waters for generations — more than any other President.

Though the celebration is happy and well-deserved, we cannot avoid recognition of the fact that our national parks face myriad challenges, particularly from climate change. From glacial melt at Kenai Fjords in Alaska, to sea level rise in the Everglades, species loss from fires in Sequoia National Park, and even threats to the cherry blossoms here in D.C., climate change is a very real threat to this historical legacy.

This is, then, a happy occasion, but one which reminds us of difficult work ahead. I have made fighting climate change a central theme of my work in Congress, and I will continue to fight to preserve this trust for our children. National Parks are the birthright of every American, and we must continue to protect these remarkable places for future generations.

Rep. Beyer can be reached through his website at www.beyer.house.gov, on Twitter @RepDonBeyer or his office at (202) 225-4376.