HI Doctor Feldman,
Thanks for taking the time to answer my question but I am afraid you didn't quite get what I was asking. My doctor has told me that I can climb again, in fact I just got back from my climbing gym. My question was, what is considered high altitude. After all, if one lives near a huge mountain, as I do, just driving near the top of it would take me up 2000 feet in less than thirty minutes from my house.