Mountaineering tents tend to be more spacious than lightweight backpacking tents. Camping on the Kahiltna glacier requires a lot of gear, and a winter tent typically has the room to store it. Rather than force two smelly people to sleep elbow-to-elbow for weeks, a roomier design allows expedition partners some personal space, plus room for duffels full of warm layers. This is where tents labeled with a three-person capacity is a little tricky: it means that it can fit two people and a lot of stuff comfortably, but three people in a pinch and all the stuff elsewhere.

As part of the additional space, tents for winter camping usually come with flys that extend out to create one or more vestibules. This is key, because a vestibule serves as a protected space to sit and remove your boots before crawling into the warmer and dry interior. If a storm is raging, it can be a relief to zip the vestibule closed while taking care of this chore. The vestibule also makes a great little room for storing extra items not needed in the tent overnight.