A survival shelter can be something you build, with tools or barehanded. It can also be something you find, ready-to-use and provided by nature. Since exposure is one of the top threats in a wilderness survival setting, learning how to find shelter quickly can save your life. The landscape can provide many different kinds of shelters if you just know where to look.
Caves are one of our oldest known human habitations, and there’s good reason for it. You’re out of the wind in most cases, unless the cave has its own air flow. You’re out of the rain and water is not a problem, unless the cave is prone to flooding. Caves also have stable temperatures, feeling cool in the summer and warm in the winter. In fact, when you get a few feet underground, the temperature doesn’t change much at all. The underground temperature will be affected by the area’s latitude, with caves in North America ranging between 40 to 60 degrees (being warmer in the south and cooler up north). Caves are also easier to defend than most other natural shelters (or man-made shelters, for that matter). They are not without problems, however. The three main issues with cave safety are animals, air and collapse.