A fascinating look at Walt Disney’s last, unfinished project and the controversy that surrounded it.

It was going to be Disneyland at the top of a mountain. A vacation destination where guests could ski, go ice skating, or be entertained by a Disney Imagineer-created band of Audio-Animatronic bears. In the summer, visitors could fish, camp, hike, or take a scenic chairlift ride to the top of a mountain. It was the Mineral King resort in Southern California, and it was Walt Disney’s final passion project. But there was one major obstacle to Walt’s dream: the growing environmentalist movement of the 1960s.

In Disneyland on the Mountain: Walt, the Environmentalists, and the Ski Resort That Never Was, Greg Glasgow and Kathryn Mayer provide an unprecedented look inside the Mineral King saga, from its origins at the 1960 Winter Olympics to the years-long environmental fight that eventually shut the development down. The fight, which went all the way to the Supreme Court, reshaped the environmental movement and helped to put in place long-reaching laws to protect nature. Although the court battle, coupled with Walt’s death in 1966, meant the end for the Mineral King resort, the ideas and planning behind it have permeated throughout the Walt Disney company and the ski tourism industry in ways that are still seen today.

With firsthand interviews and behind-the-scenes details, Disneyland on the Mountain offers incredible access to a part of Disney history that hasn’t been thoroughly explored before, including Walt’s love of nature, how the company changed after Walt’s death, and of course, the story of Mineral King. It’s a tale of man versus nature, ambition versus mortality, and how a gang of scrappy environmentalists took on one of America’s most beloved companies.