In the late 1800s, Americans looked inward and saw rare landscapes that needed to be saved. In the process, the country invented a park system that has inspired generations.
From California's towering sequoias to Maine's craggy coast, we celebrate five awe-inspiring national parks.
Marine scientist Rick Hamilton embarks on a search for a deep-water nautilus not seen in decades.
Three Natural Wonders to See This Year
The Nature Conservancy has played a role in protecting parks across the United States.
The Nature Conservancy's global managing director for public policy speaks to the value of our national parks.