Dutch Lower Saxony is known for its low, rolling hills, lowland forests, polders with terpen and wierden in the northern provinces, and the Wadden Sea, which is home to a large variety of migratory birds. It is also well-known for its unique governmental position, being an integral part of Saxony despite having the King of the Netherlands, currently Willem-Alexander, as head of state instead of the President of Saxony. Due to its maritime position, Dutch Lower Saxony has an oceanic climate. The state capital is Amersfoort; the largest city is Groningen.