Smell - The sense of smell overwhelms me every time I go for a hike. I was just explaining to someone about my hidden likeness for the smell of skunk cabbage. Flowers and trees give off very potent, wonderful aromas that are masked in everyday urban life by things like exhaust or other pollutants. Because your senses can steal from each other like jumping ahead in line, you might not smell something because of too much noise for example. This usually is not a problem on a long walk in the woods.

Sight - Simply put, there are things you will see on a hike that cannot be seen otherwise. Very few roads will take you to the top of mountain peaks or alpine meadows. One of my favorite parts of a high alpine hike, is seeing the slow transition from forest to a meadowy hillside. Lakes are not visited by boats or jet skis and therefore, a person can look to the bottom of most of them, and sometimes even see that blue, glacial tone in.

Sound - Sometimes rivers can be heard from far away while walking on a ridge high above them. Many different birds call out as you pass them, but marmots take the cake on animal calls as my favorite sound out there. Snow or rocks avalanching down a hillside from afar can sometimes be heard. There are so many thing to hear when you cut out the sounds of a normal city day.

There wasn't always seven billion people on the planet. There are systems of trails that are only being used by a small percentage of people. Some may say they hike and even check that box on a survey, but only find a path through the woods every couple of years. Having been on a backpacking trip and not having seen another person up close for three consecutive days, I have felt something that a very small percentage of the other seven billion people have felt. A person can realistically find themselves lost at sea on purpose out in the mountains.

Even if you find yourself on a crowded trail, you will most likely not see a tenth of the people you would have in the city. The great thing about others on the trail is that they are very friendly and best of all - they know you are friendly too!

If I had to come up with an exact reason for hiking, it would be because of the chance against running into someone in a bad mood. In everyday life there can be too many people with too many different goals multiplied by way too many emotions. We all have similar goals on an incline to a beautiful lake, just as we all have the same goals on the way back down a trail from the top of a mountain. This means that a person is guaranteed to have a lot in common with others out there away from it all!

A friend used to call out, while cresting a pass or in the middle of climbing a series of switchbacks to a mountaintop, "I got hiker's high!" This was his way of describing a feeling of bliss mixed with adrenaline from his exertion. Though I don't usually call it out, I too get hiker's high and recommend it as a prescription to heal a down and out mental state.

Here is another look at the same question by one of my favorite bloggers! http://sticksblog.com/2014/10/05/why-do-i-hike/