This week, three people have died hiking Arizona trails. Others have required rescue. A Valley hiking expert said avoiding these dire situations comes down to a few key things.

Food, sun protection, navigation. Those are a few of the so-called “10 essentials” that hikers are encouraged to have, even if they’re just out for the day.

Chuck Vaughn is an outdoor instructor at REI and has been hiking Arizona trails for a decade. He said people often think just because they live here and are used to the weather, they should have no problem hiking.

"But once you get out into the desert, on a trail with the amount of exposure you have, and the fact that you can’t go inside for half an hour and grab a cold glass of water, or sit in the air conditioning," he said. "It makes a big, big difference."

And one of the biggest things hikers can do to prepare, he said, is bring water — lots of it. Vaughn figures about a liter per person, per hour. But he always brings more.