Earthlodges 

Designed to protect occupant from elements and enemies.  Each round lodge held several families.  Each family had its own bed or beds next to the outer wall.  A fire ring was located in the center, under a smoke hole in the ceiling which was covered with a twig screen. 

October 27, 1804 Clark's Journal Entry describes the lodge:
" ... the houses are round and very large containing several families, as also their horses which is tied on one side of the entrance"

PICTURE SOURCE: (State Historical Society of North Dakota)