Glacier, Wrangell-St. Elias National Park, Alaska, 2003Photograph by Frans LantingStreams of ice flow together like rivers, forming glacier complexes that cover hundreds—sometimes thousands—of square miles in Wrangell-St. Elias National Park. Covering more than 13 million acres (5.2 million hectares), Wrangell-St. Elias is the largest national park in the U.S. Nearly six Yellowstones could fit within its borders.