A tundra is a vast, treeless region found in the coldest parts of the world, where the ground stays frozen for most of the year and only small, hardy plants can survive.

In the Arctic tundra, which stretches across northern Canada, Alaska, Russia, and Scandinavia, the soil beneath the surface, called permafrost, remains frozen year-round. During the brief summer, the top layer thaws just enough for mosses, lichens, low shrubs, and wildflowers to grow close to the ground. These tough little plants can withstand fierce winds and temperatures that would kill an oak tree or rose bush.

The tundra might look empty, but it supports caribou, arctic foxes, snowy owls, and millions of migrating birds that arrive each summer to nest and raise their young. Indigenous peoples like the Inuit have lived on the tundra for thousands of years, developing remarkable skills for surviving in such an unforgiving environment.

There's also alpine tundra, found on high mountains like the Rockies, where it's too cold and windy for trees to grow even though you're not near the Arctic. Whether in the far north or high on a mountain, tundra represents one of Earth's toughest environments, where only the most resilient life can take hold.