As more and more parents venture to altitude, children accompany them to altitudes of 18,000 feet (5500 meters) or so, without ill effect. A leisurely itinerary is important. Children aged three and seven have hiked to the top of Kala Pattar (18,450 feet, 5620 meters). A three-and a half year old was successfully treated for symptoms of lethargy in a hyperbolic bag. It is difficult to identify symptoms and signs of altitude illness in children. Altitude localities are cold and remote, making evacuation worrisome. Consider any questionable behavior at altitude to be altitude illness. Descend quickly and few problems should result.