The Trump administration has initiated steps to redefine what it means to "harm" a threatened or endangered species, a move that could jeopardize the effectiveness of the Endangered Species Act, according to the Center for Biological Diversity.

Yellowstone volcanism has produced some of the youngest rocks in North America. This same region also features some of the most ancient rocks in North America—as old as 3.96 billion years in the Beartooth Mountains to the northeast of Yellowstone caldera.

National Park Week kicks off April 19 and runs through 27 with plenty of special programming for visitors.

Voyageurs National Park in Minnesota commemorates those French-Canadian fur traders (voyageurs), the first Europeans to travel through the area with their canoes 250 years ago. Indeed, while there are a few visitor centers and trails that can be reached by car, the best way to explore the 218,000 acres of lakes, rivers, and forests is by boat.