With 362 species per 100 square kilometers, Congaree's bottomland hardwood forest and waterways support a rich ecosystem.
Congaree National Park, South Carolina
Hosting 317 species per 100 square kilometers, this park features oak-hickory forests and wetlands.
Cuyahoga Valley National Park, Ohio
Home to 286 species per 100 square kilometers, including the famous Brazilian free-tailed bats.
Carlsbad Caverns National Park, New Mexico
With 255 species per 100 square kilometers, witness the remarkable recovery of the California condor.
Pinnacles National Park, California
With 242 species per 100 square kilometers, enjoy seals and shorebirds along Maine's rugged coastline.
Acadia National Park, Maine
Hosting 235 species per 100 square kilometers, this park is a refuge for bison and elk.
Wind Cave National Park, South Dakota
Despite its name, this park is 99% water and hosts 223 species per 100 square kilometers.
Dry Tortugas National Park, Florida
Hosting 217 species per 100 square kilometers, explore the world's longest cave system.
Mammoth Cave National Park, Kentucky