Check out this one. Absolutely brilliant for me, only one pole needed. That's what I would use in the mountains. Ventilation through the "floor" I would imagine. I can only imagine the size with my 3,6x3...
http://www.youtube.com/watch?v=IcoCNzDi8nY
http://www.youtube.com/watch?v=7VF34Jhx7hM
http://www.youtube.com/watch?v=IcoCNzDi8nY
http://www.youtube.com/watch?v=7VF34Jhx7hM