Yosemite National Park
Est. 1984 | California
Why it's UNESCO-worthy: The park is best-known for its double Gs: glaciated granite. The eons-old erosion resulted in a wonderland of waterfalls, including five of the world's tallest; polished domes; toothy peaks; and precipitous cliffs. Giant sequoia groves and alpine meadows soften all the hard stuff.
How to reach it: San Francisco is four to five hours away by car. Even closer: Mariposa, California, which is less than 45 miles from the Yosemite Valley Visitor Center. Amtrak offers rail-and-bus service to Yosemite Valley.
Best time to visit: April and May, when the snow melts and the waterfalls roar to life.
Insider tip: View Yosemite through the lens of Ansel Adams on a free Camera Walk led by the staff of the Ansel Adams Gallery during the summer.
Monumental Earthworks of Poverty Point
Est. 2014 | Louisiana
Why it's UNESCO-worthy: Hunters, fishers and gatherers constructed the ancient settlement 3,400 years ago on Macon Ridge, which overlooks the Mississippi River flood plain. Native Americans moved the soil by hand to construct mounds, C-shape ridges and a large central plaza. The "cultural capital" was a center of trade, commerce, ceremonies and catching up with friends.
How to reach it: The site is in Pioneer, Louisiana, about 100 miles west of Jackson, Mississippi.
Best time to visit: The seasons bookending Louisiana's sauna summer.
Insider tip: Scale the 72-foot-tall Mound A, known as the Bird Mound, the second-largest mound by volume in North America.