I have just come from a 1 week trip to Leh Ladakh, Leh National Highway is the highest motorway in the world, the level of oxygen there is so low that breathing becomes difficult, my condition there became so bad that a At that moment I felt absolutely dead, deep breathing kept me alive and we quickly reached the lower area, My oxygen level had gone up to 68, and I had to take oxygen at the Army Medical Camp. Inner Line Permit is made in Ladakh. It is mandatory written on it that every tourist must keep Diamox 250 tablets with him. And it has to be consumed in the morning and evening, otherwise the situation can be life threatening.