Northern Germany () is a linguistic, geographic, socio-cultural and historic region in the northern part of Germany which includes the coastal states of Schleswig-Holstein, Mecklenburg-Vorpommern and Lower Saxony and the three city-states Berlin, Hamburg and Bremen. It contrasts with Southern Germany, Western Germany and Eastern Germany. Language Northern Germany generally refers to the Sprachraum area north of the Uerdingen and Benrath line isoglosses, where Low German dialects are spoken. These comprise the Low Saxon dialects in the west (including the Westphalian language area up to the Rhineland), the East Low German region along the Baltic coast with Western Pomerania, the Altmark and northern Brandenburg, as well as the North Low German dialects. Although from the 19th century onwards, the use of Standard German was strongly promoted especially by the Prussian administration, Low German dialects are still present in rural areas, with an estimated number of five to eight million active speakers. However, since World War II and the immigration of expellees from the former eastern territories of Germany, its prevalence has steadily reduced. Besides which, Frisian is spoken in East and North Frisia, as well as Danish (Standard and South Jutlandic) in parts of Schleswig. From a linguistic and cultural perspective, Northern Germany is linked to the Netherlands, Scandinavia and England. For example, the German word for butcher is Fleischer or Metzger in the middle, east or south of Germany but is called a Schlachter in Northern Germany, resembling the Scandinavian terms for butcher, slagter/slakter. Other examples are the word for potato, which has historically been Erdapfel in much of Southern Germany, Austria and Switzerland, but Kartoffel in Northern Germany and in Danish; the North German verb kieken (meaning to look), resembling the Danish kikke/kigge, or Norwegian kikke (to look); or the word for the fruit orange, which is Orange in standard German, but Apfelsine in Northern Germany, similarly to the Dutch (appelsien/Sinaasappel), Frisian (aapelsiin) and Scandinavian languages (appelsin/apelsin). Additionally, Jansen/Janssen, Hansen, and Petersen are the most common surnames in the far north of Germany (Lower Saxony and Schleswig-Holstein), which are also some of the most common surnames in Denmark (albeit with Jensen for Jansen). Hansen is the single most common surname in Norway, the third most common surname in Denmark, and the third and fifth most common surname in the North German federal states of Schleswig-Holstein and Hamburg, respectively. Geography The key terrain feature of Northern Germany is the