Always set a “Turn Back Time.”
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HIKING TIP #2
Carry a Reserve Bottle of Water. Or maybe two.
Camelbak and other reservoir-style hydration packs make carrying and drinking plenty of water on the trail much easier and convenient. However, it's sometimes hard to determine how much water you actually have left without dropping your pack and actually looking at the water bladder. Camelbak has come out with an electronic flow meter but I'm not sure I want to deal with one more battery-operated gadget on the trail. Generally speaking, you should carry/consume about 1 qt of water per hour of hiking. Variables such as air temperature, sunny or shaded trails, body type and other such things will affect how much you'll actually drink. In the event that my pack's reservoir runs dry before anticipated, I carry a few extra bottles of water in the bottom of my pack. Knowing I've run out of water might help me make decisions to cut a hike short, slow my pace or seek out alternate sources of water immediately. I've used the extra water only once, but the peace of mind it provides has always been there.
HIKING TIP #3
Make a Fire Starting Kit. And carry it with you!
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All of this is kept in a waterproof container and carried in the bottom of a day pack. Consider carrying a Bic lighter (or two) as well, especially if you're going to be hiking longer than just a short day hike. I occasionally use a few of the matches to light my camp stove to keep the emergency stock fresh and ready to go when needed.
HIKING TIP #4
PBJ Sandwich Construction
When making a peanut butter and jelly sandwich for your day hike, put a smear of peanut butter on both slice of bread with jelly in-between those layers. This prevents the jelly from soaking into the bread, making the sandwich mushy by the time you enjoy it later one.