A hillock or knoll is a small hill, usually separated from a larger group of hills such as a range. Hillocks are similar in their distribution and size to small mesas or buttes. This particular formation occurs often in Great Britain and China. A similar type of landform in the Scandinavian countries goes by the name "kulle" or "bakke" and is contrary to the above phenomena formed when glaciers polish down hard, crystalline bedrock of gneiss or granites, leaving a rounded rocky hillock with sparse vegetation.