Von Thünen's model from 1826 describes six concentric zones of agricultural land use radiating from a central market. The first zone consists of market gardening activities for heavy, bulky products like vegetables. The second zone is dairy farming as milk spoils quickly. The third zone is livestock fattening in feedlots. The fourth zone is commercial grain farming. The fifth zone is livestock ranching. The sixth zone is non-agricultural land too far from the market. The model assumes uniform land quality, transportation access, climate, and political factors.