George B. Hartzog Jr., the seventh director of the National Park Service, died on Friday. He was 88 years old.

During his nine-year tenure, 1964 to 1973, Hartzog led the largest expansion of the National

Park System in its history, according to an NPS news release.

During those nine years, 72 sites were added to the national park system, sites that included national parks, historical and archeological monuments, recreation areas, seashores,

riverways, memorials, and cultural units comemmorating minority experiences.

Here is more from today’s news release:

"George Hartzog was one of the great champions of the National Park Service," said NPS Director Mary A. Bomar. "His vision of what the national parks should be and should mean to the American people left an indelible mark on the agency he so loved and believed in. His goal of making the National Park Service relevant to people who previously had been overlooked, especially minorities and women, has strengthened our agency."

"I was fortunate to have known Mr. Hartzog, he truly inspired me early in my career as he did so many others who knew him through the impact of his legacy. Once I assumed my directorship – we got to know each other personally then I found myself truly inspired by him — his big ideals of

public service, as well as his passion for the National Park Service and its employees. My special memory of him was at the White House this past Christmas celebrating our National Parks — he was so happy at that event. Our hearts go out to his wife Helen and their children who I know will miss him greatly. His National Park Service family will miss him too, but we all thank him for helping make us what we are today."

Hartzog joined the NPS in 1946, when he entered the service as an Attorney. Field assignments as assistant superintendent at Great Smoky Mountains and Rocky Mountains national parks came along soon after. While serving in St. Louis, he brought to completion one of America’s most recognizable landmarks, the Gateway Arch.

Former Secretary of the Interior Stewart Udall noted “Hartzog was able to leave behind a legacy that to this day is unsurpassed in the amount of land acquired, and the amount of legislation passed to protect public lands." He described Hartzog as a reminder “of the glories of public service and

the legacies our best bureaucrats leave to future generations.”