President Donald Trump on Tuesday signed into law a major public lands bill that will pump hundreds of millions of federal dollars into Colorado’s national parks.

“This is a very big deal,” the president said in the East Room of the White House. “From an environmental standpoint — and just a beauty of our country standpoint — there hasn’t been anything like this since Teddy Roosevelt, I suspect.”

The Great American Outdoors Act permanently funds the Land and Water Conservation Fund, which has been chronically underfunded for decades. The fund uses oil and gas revenue to expand public lands, safeguard natural areas and protect cultural heritage sites. LWCF has invested about $300 million in Colorado.

The bill also addresses a $20 billion backlog of deferred maintenance in national parks. Rocky Mountain National Park has a backlog of $84 million, for example.

The Senate version of the bill was sponsored by Sen. Cory Gardner, R-Yuma, and co-sponsored by Sen. Michael Bennet, D-Denver. It was Gardner who convinced a reluctant Trump in March to back the bill, clearing it for passage through Congress.