#plain__champaign  extensive tract of level open land; "they emerged from the woods onto a vast open plain"; "he longed for the fields of his youth"
  supertype:  dry_land__dryland__land__earth__solid_ground__solidground__terrafirma  the solid part of the earth's surface; "the plane turned away from the sea and moved back over land"; "the earth shook for several minutes"; "he dropped the logs on the ground"
  instance:  Olympia
  subtype:  flat  a level tract of land
     subtype:  salt_flat__salt_plain  a flat expanse of salt left by the evaporation of a body of salt water
  subtype:  llano  an extensive grassy and nearly treeless plain (especially in Latin America)
  subtype:  moor__moorland  open land usually with peaty soil covered with heather and bracken and moss
  subtype:  snowfield  a permanent wide expanse of snow
  subtype:  steppe  extensive plain without trees (associated with eastern Russia and Siberia)
  subtype:  tundra  a vast treeless plain in the arctic regions between the ice cap and the tree line

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