Exploring nature on foot is a sure way to observe all the truly wonderful details of the world around you, from sweeping vistas to dainty little flowers half-hidden among the rocks. And no restaurant on earth can offer better seating than a mossy rock beside a swift-flowing mountain stream, munching your lunch while getting a free mood boost from the negative ions produced by the running water.
Arduous hiking trails aren't for everyone. People who are unaccustomed to walking or exerting themselves should choose a trail that doesn't have any long, steep elevation changes or one that has a reasonably smooth, uncluttered treadway (trail surface) with minimal rocks or protruding roots to trip you. Doing a little research ahead of time ensures that you'll have an enjoyable hike.
Topographic Maps and Terrain
Even more experienced hikers should check out the terrain ahead of time on a good topographic map that shows the trails and trailheads. Take anything you hear with a grain of salt. I once heard a visitor center employee describe a nearby hiking trail as "easy." Well, I had hiked that trail before and knew that, although it was short as far as such trails go, about four miles round-trip, it was rather steep and rocky. I would have rated it as "moderate" at the very least, and I'm a seasoned hiker.
Total elevation change doesn't really provide much information. A guidebook may describe a particular trail as having a total elevation gain of, say, 1000 feet, but it may ascend 2000 feet and then descend another 1000 feet. That gives a total gain of 1000 feet, but your tongue will be dragging long before you reach the top. Learning to read a topographic map is one of the best skills you can develop if you're serious about hiking.
Trails are usually rated as easy, moderate and difficult, taking into account elevation gain and roughness of the treadway. Consider whether the trail crosses streams or whether you have rivers to ford along the way. Verify how well traveled the trail is and whether it's properly marked. In wilderness areas, blaze marks tend to be few and far between and the trails themselves are more rugged and less traveled.
The time of year is also worth taking into consideration. In the spring, creeks and streams run higher than during other seasons, so you need to plan your route accordingly. A small creek in the summer could be high and fast enough to knock you off your feet in the spring.
Even if you're going for only a short day hike, wise hikers carry a day pack to hold a few essentials. Your pack should include a small first-aid kit, compass, topographic map (that you should have learned to read before starting your hike), high-energy snacks, plenty of water, matches or some form of fire-starter, and a Swiss Army knife or multi-tool. Take along pain killers and any medication you can't live without should you be caught out longer than you expected. Pack some rain gear.
Don't even think about a cell phone. My experience with areas traversed by hiking trails is that signals tend to be either weak or non-existent there. With matches you can at least make a smoke signal if you get in trouble, or a fire to provide warmth and protection if you get lost and have to spend the night out in the open.