Large group shelters that are very strong, relatively light, and easy to pitch are difficult to find. The Hilleberg Atlas Group Shelter is all these things and more, since it is also totally modular. The people at Hilleberg originally designed and built the Atlas for polar scientists who wanted a mobile research station, and it has been used with great success by South Pole research teams for over seven years. It appeals to large backcountry groups of all types, from mountaineering expeditions needing a highly reliable, spacious base camp tent to outdoor programs looking for large, easily portable spaces for sleeping and group gathering. It has also become especially popular with outfitters leading large groups into remote places. The Atlas can be used in its Basic form, with no inner tent or floor, or it can be customized as needed with a variety of options. The Inner Tent 8 and 6 (Sold Separately), which sleep eight and six persons, respectively, both have sewn-in floors. The Floorless Inner (Sold Separately) also sleeps eight, and can be paired with the Detachable Floor (Sold Separately), which can also be used without the inner tent. External Vestibules (Sold Separately) can be added to either door, and the Connector (Sold Separately) can join multiple Atlas tents together. And the optional Carrier Bag (Sold Separately) is designed to function as a backpack for transporting an Atlas and all its optional components in a compact, easy-to-carry package.