A double wall tent is any tent that has two layers or walls. Usually the fabric of the tent forms one layer that may have mesh or no-see-um windows for ventilation and visibility and a second layer that serves as the the rainfly to protect from the elements. It may include a vestibule at the entrance to keep equipment out of the weather. Double wall tents usually have windows on the inner wall, which can provide ventilation when the rain fly is in use as some air can usually flow under the rain fly. When rain, wind or snow are not an issue, a single wall tent can be pitched without the rain fly to provide better ventilation and views of the night sky depending on window placement.