President Barack Obama added to his conservation legacy Tuesday when he cancelled the two remaining oil and gas leases in the Badger-Two Medicine area.

Department of the Interior Secretary Sally Jewell announced Tuesday that the Bureau of Land Management had cancelled the leases owned by J.G. Kluthe Trust of Nebraska and W.A. Moncrief Jr. of Texas and would reimburse them for payments associated with the leases. Neither lease had been developed.

“We are proud to have worked alongside the Blackfeet Nation and the U.S. Forest Service throughout this process to roll back decades-old leases and reinforce the importance of developing resources in the right way and the right places,” Jewell said. “The cancellation of the final two leases in the rich cultural and natural Badger-Two Medicine Area will ensure it is protected for future generations.”

The Blackfeet tribe and conservation groups celebrated the news.

“It’s impossible to overstate just how many people have worked over the decades to get these leases cancelled. They come from all walks of life and are driven by the shared conviction that certain places, like the Badger-Two Medicine, are simply too biologically- and culturally-rich to drill,” said Kendall Flint, Glacier-Two Medicine Alliance president.

The Blackfeet have been fighting the leases for more than 30 years, arguing that even though the Badger-Two Medicine is outside their reservation, it is sacred land that holds cultural and religious importance. The leases were initially sold in the 1980s but then exploration was stalled as lawsuits were filed andthe government conducted study after study.

Finally in September 2015, the independent Advisory Council on Historic Preservation heard dozens of tribal members tell their stories and ultimately agreed that the U.S. Forest Service shouldn’t have opened the area to leasing in the first place.

In November 2016, the BLM officially cancelled the 16 leases belonging to Solenex LLC and Devon Energy. Solenex subsequently sued to be allowed to develop its lease. That could be a problem for the Badger-Two Medicine as an oil-friendly administration prepares to take over on Jan 21.

“The fight is not over,” said Tim Preso, managing attorney at Earthjustice’s Northern Rockies region office. “We will continue to advocate for this wild and sacred landscape until the last threat to its integrity is removed.”

The Badger-Two Medicine lease cancellations follow on the heels of Obama’s decision to set aside as a national monument the Bears Ears in Utah, another area that is sacred to five tribes.

On Saturday, more than 400 supporters turned out to celebrate the designation of the 1.3-million-acre Bears Ears Monument. That brings the total land area protected by the Obama administration to 6,250 square miles, which includes 22 new properties to be managed by the National Park Service.