These phones are connected to the park's 24-hour dispatch center and do not require coins. Please remember that fatigue is not an emergency. Risks are greater for those who hike alone. There is no one to assist you if you become lost, ill, or injured. Mountain lions do inhabit the Grand Canyon.
Hikers traveling alone are at greater risk of attack.
Be sure to keep your group together, a good plan is to have your most skilled members at the front and rear of your group with the novices in the middle. To do otherwise is littering. When in camp, be sure to hang your trash with your food sack to prevent its being scattered by wildlife. Be prepared to provide your own toilet paper. Where toilets are available, you must use them.