霞ヶ浦
In a narrower sense and officially, Lake Kasumigaura refers to a waterbody with an area of 167.63 km2. In a wider sense, Lake Kasumigaura can also refer to a group of contiguous lakes, which includes Lake Kasumigaura proper, hereby referred to as Nishiura (西浦), and two smaller lakes, Kitaura (北浦; 35.16 km2) and Sotonasakaura (外浪逆浦; 5.85 km2), and also encompasses the rivers connecting them. In this case the total area is 220 km2.