Oh, I'm guessing a 1000m to 1500m ... really not that sure so. I only do day tours here in the Interior of BC (Cariboo Mountains) and usually start out at an elevation of around 1100 to 1300 meters. Most mountains around here are 2000 to 2300 meters high. But then it depends more on conditions than overall climbing elevation, if you have a track you are going pretty fast, if you have to skin up through fresh snow its pretty tiring.

 Thats why we invented ski lifts
Jokes - I guess it keeps you fit right?