After hearing all the horror stories from the above respondants, about the hazards of 8-9-10,000' elevations Im stupdified. Apparently those altitudes cause sleeplessness, headaches, nausea, impotence, and pre mature tire wear. This is quite a relief to finally know its not actually me but the altitude that is causing all my problems. I live at over 9000' elevation and regularly work at up to 12,000'. All these years my wife and kids thought it was just me being wierd. Having lived and worked here all my 50 + years and being on local rescue teams I can suggest the following. A good spacebag and a mini 6oz wind and waterproof tent, plenty of water and high energy snacks. And most of all one of the new personal distress locator devices. These help rescuer find you in minutes instead of days if hurt or ill.