Yellowstone and Glacier national parks are competing against 18 other national parks across the country for title of Best National Park.
10Best, which is a division of USA Today Travel, is asking readers to vote on which park deserves the award.
According to the 10Best website, the poll aims to "pit mountains against canyons, lakes against rivers and coasts against prairie."
The experts who chose the 20 nominees, David and Kay Scott, said Yellowstone made the list because it's America's first national park, and one of the most iconic.
"Home to the world's largest collection of geysers, including the famous Old Faithful," they said, "Yellowstone attracts some 3 million visitors a year to its bizarre geological formations and teeming wildlife, including bison, bear, bighorn sheep, trumpeter swans, moose, elk and river otter."
When it came to Glacier, they said they liked that park because it offers something for everyone.
"Hikers come to explore the 700-mile network of trails. Road trippers and motorcyclists come to ride the curves of Going-to-the-Sun Road, and engineers come to marvel at it," the duo said. "The massive, snowy peaks of the Continental Divide hide azure alpine lakes, colorful patches of wildflowers and the occasional cascading waterfall."
Voters can submit their choice daily until July 14th, by clicking here.