The geologic history of Glacier National Park is read in the numerous exposed layers of Precambrian sedimentary formations. These extremely well preserved sediments date back to over 1 bilion years. Subsequent sculpting by massive bodies of ice has transformed this area into a dramatic example of glacial landforms. Today several small alpine glaciers of relatively recent origin dot the mountains. Due to its geographic location and geologic history, Glacier National Park contains a particularly rich biological diversity of plant and animal species. This combination of spectacular scenery, diverse flora and fauna, and relative isolation from major population centers have combined to make Glacier National Park the center of one of the largest and most intact ecosystems in North America.

Glacier National Park and Waterton Lakes National Park in Alberta were joined together by the governments of Canada and the United States in 1932 as Waterton-Glacier International Peace Park, the first park of its kind in the world. Both parks have been designated Biosphere Reserves. In December of 1995 they were jointly designated the "Waterton-Glacier International Peace Park World Heritage Site."