Kiel Fjord in the context of "Kiel Canal"

The Limes Saxoniae (Latin for "Limit of Saxony"), also known as the Limes Saxonicus or Sachsenwall ("Saxon Dyke"), was an unfortified limes or border between the Saxons and the Slavic Obotrites, established about 810 in present-day Schleswig-Holstein.

After Charlemagne had removed Saxons from some of their lands and given it to the Obotrites (who were allies of Charlemagne), he finally managed to conquer the Saxons in the Saxon Wars. In 811 he signed the Treaty of Heiligen with the neighbouring Danes and may at the same time have reached a border agreement with the Polabian Slavs in the east. This border should not be thought of as a fortified line, however, but rather a defined line running through the middle of the border zone, an area of bog and thick forest that was difficult to pass through. According to Adam of Bremen's description in the Gesta Hammaburgensis ecclesiae pontificum about 1075, it ran from the Elbe river near Boizenburg northwards along the Bille river to the mouth of the Schwentine at the Kiel Fjord and the Baltic Sea.

The Bay of Kiel or Kiel Bay (German: Kieler Bucht, German pronunciation; Danish: Kiel Bugt) is a bay in the southwestern Baltic Sea, off the shores of Schleswig-Holstein in Germany and the islands of Denmark. It is connected with the Bay of Mecklenburg in the east, the Little Belt in the northwest, and the Great Belt in the North.

Maritime traffic entering or leaving the Baltic through the two Belts must enter the bay. Once in, through traffic to the Baltic passes through another strait, the Fehmarn Belt, into the Bay of Mecklenburg, which opens out into the Baltic Sea. In the other direction, traffic can either pass northward through the Great Belt, keeping Langeland on the port side, or enter the Kiel Fjord and traverse the Kiel Canal directly to the mouth of the Elbe River and the North Sea. The Kiel Fjord ends at Kiel, the capital of Schleswig-Holstein.

The Schwentine (German pronunciation: [ʃvɛnˈtiːnə]) is a river in the North German state of Schleswig-Holstein. It is approximately 62 kilometres (39 mi) long and rises on the hill of Bungsberg, the highest point in the state, near the village of Kasseedorf in Ostholstein. It then runs from its source to Kiel where it flows into the Kiel Fjord, a bay of the Baltic Sea. It passes through several lakes, including the Großer Plöner See, the largest lake in Schleswig-Holstein, as well as the towns Eutin, Malente, Plön, Preetz and Kiel.