Located in a remote part of a Louisiana wildlife refuge, this tree has been standing for more than 1,200 years.

A miscalculation turns a very shallow freshwater lake into a very deep saltwater lake.

A swamp and garden tour featuring local wildlife and exotic botanical specimens from around the world.

This magical oasis in East Texas is one of the most biodiverse acres in the country.

The largest underground pedestrian tunnel system in the U.S. mostly caters to the people working in the offices above, but provides a great, air-conditioned way to traverse the city.

A chimney and a plaque are all that remains of a logging camp that once cleared out a large swath of Minnesota's old-growth forest.

A spiralling hourglass-shaped tower rises from the forests in Denmark.

A resilient tree that has survived for more than 700 years in Guánica Dry Forest.

These small, spectacular monkeys are making a comeback after deforestation destroyed much of their rainforest habitat.

Twisted trees shaped by coastal winds make this woodland look like something from a spooky story.

A reservation-only highland forest reserve of endangered Pinsapar firs stands above a village in Andalucía.

A fire lookout atop a glacial pinnacle is reached by climbing three vertiginous flights of stairs.

A 14th-century abbey founded by a forest-loving order of monks now sits in the center of a pristine nature preserve.

A little-known occurrence of fossil wood in northern Washoe County, Nevada, near the Black Rock Desert.

An eccentric memorial garden to the "warrior" birds of World War I, the messenger pigeons used by the Allied forces.

This unique bird reserve sits within an important fragment of Brazil's Atlantic rainforest.

Swim alongside softshell turtles in these turquoise waters within the Cuatrociénegas Biosphere Reserve.

The damming of the Colorado River buried an iconic geologic formation before record-breaking drought brought it back.

An underground river pushes more than 200 million gallons out of this Missouri spring every day.

Amid rushing rapids, this small bit of land is an important First Nations site on border between Canada and the United States.

This medieval footbridge in the Swiss Alps is known to attract cliff-jumping daredevils.

It's as if the herds walked straight out of a fairy tale into the Missouri wilds.

The origin of these small islands' sweet names is a local mystery.

This functioning mill was built in the 1970s using parts from several other West Virginia mills.