For those hardy few who want to make the full hike, the physical and mental demands are intense. Travel down into the Canyon is the "easy" part -- the opposite of a mountain ascent, of course -- but it means a lot of punishment for your knees and legs, as well as the possibility of heatstroke and other hiking mishaps. The most prepared and experienced hikers train months for the hike ahead of time, often for as long as eight months to a year.
The Canyon, though cold at night and on the northern side, works like an oven during the daytime, and Arizona's dry heat means you won't even notice your sweat instantly evaporating. While most of us can easily imagine the physical punishment -- or think we can -- these qualities specific to the canyon need to be factored in as well.
Along with planning the details of your overnight stays, which we'll discuss later, you also need to consider these details when planning what to bring: A gallon of water per person per day, food to eat that won't slow you down or make you sick, changes of clothes and first aid needs, and balance all of it against the fact that you'll be carrying everything with you. While the Grand Canyon's famous mules can be rented by the day, taking off a bit of the pressure, you're still going to need to be very clear with yourself about the demands this adventure will make on your body. It's a workout for your muscles, your mind, your vascular system and every other part of you.
At the end of this article, you'll find links to several personal accounts of rim-to-rim hiking trips that will help you imagine the physical challenges you'll find in the canyon. Note the amount of blisters, vomit attacks and tears. Reading these accounts should help you be realistic with yourself about your capabilities, and keep you from being one of the 250 people that needs rescuing every year [source: National Parks Service].