William Whalen, a former director of the National Park Service who oversaw the doubling in size of the national park system, died September 28 in Ross, Calif. of a heart attack. He was 66.

Whalen led the agency from 1977 to 1980. He was best known for implementing the Alaska Native Lands Claims Settlement Act, which led to the establishment of 10 national parks and expansion of several others in 1980. The 44 million acres effectively doubled the size of the national park system.

Whalen, then 36, was the youngest director in the agency’s history when President Carter appointed him in 1977.

Colleagues considered Whalen a visionary who brought an emphasis on urban parks to an agency that had been focused on icons such as Grand Canyon and Yellowstone national parks.

He also oversaw the creation of more than 30 parks, including the Martin Luther King Jr. National Historic Site.

In 1980,Whalen was fired, partly because of friction with private concessionaires who complained about his attempts to upgrade food and lodging to cope with a growing tide of 268 million annual visitors to more than 320 national parks and monuments.

“Bill had promising gifts, some of which desert him at awkward times. He once lectured the park concessioners, a contentious group, as if they were schoolboys,” wrote Bill Everhart in “Take Down Flag & Feed Horses,” a 1998 book about working at Yellowstone National Park.

Whalen’s remarks led to a rebuke by Morris K. Udall, an Arizona congressman who chaired the House Interior committee. He demanded the director be dismissed, and Interior Secretary Cecil Andrus let him go.

“My firing is a clear signal that you don’t mess around with those powerful concessionaires,” Whalen said at the time. “Park directors that stand up and do the job won’t last too long.”

He returned to Golden Gate to oversee the recreation area for two years and launched the Golden Gate National Parks Conservancy, which has raised more than $100 million for the park.