Best pant for winter hiking/cold weather activity. I wear my cirque pants every day in the field during the winter. I can comfortably wear 1-2 long underwear layers underneath, or not (I use the adjustable waist feature). I recommend these pants to anyone recreating in cold temps, I've worn them in minus 30 to 60 deg F weather comfortably. These pants have served me just as well in on cold powdery days and warmer spring slushy/post-holing days. The only thing that might make these pants better would be side leg vents, but I would continue to purchase again and again w/ out the addition.