Driving south from Reno, NV, on US Highway 395, you'll see a foothill that looks like a chunk was torn out of it. The hill is Slide Mountain; a block slide occurred: a single large mass of material gave way and slid downslope. You're more likely to encounter a fall when hiking or climbing, where rocks and boulders detach from a cliff or steep slope and roll downhill.

Landslides can and do happen in all 50 states of the U.S., and kill between 25 and 50 people each year. Major landslides and mudslides have killed hundreds to thousands of people in countries including Mexico, India, and China when slides hit populated villages. If a landslide occurs in the backcountry, it can still kill, but is less likely to if you're prepared.

To survive a landslide, you need to know where they're likely to occur, warning signs and what to do if one happens. Landslides are most common in areas where fires have destroyed ground-gripping vegetation, areas where there's lots of water, from quick snow melt or heavy rains, and areas of volcanic activity - which includes areas around hot springs and steam vents as well as actual volcanoes. Some warning signs are seepages of water in usually dry areas, new fissures in slopes or boulders, or boulders appearing farther apart or closer together.

Your first warning is an increasingly loud rumbling followed by a trickle of rocks falling around you. The rocks will be followed by more and larger material, so get out of the way. Move sideways as far and quickly as possible, then roll yourself into a small ball and hold your pack over your head. If you're the first to notice the fall, shout loudly to your party. Once the fall stops, keep calling out until your group members find each other.

If you're climbing, always wear a helmet. If you're hiking, wear sturdy boots, carry a durable and solid backpack, and carry along a jacket. Even if it's not cold, the jacket can be used to help prevent shock if someone in your party is injured.