The Eider Canal, the first connection between…

The Eider Canal, the first connection between the North and Baltic Seas, had been constructed while the area was ruled by Denmark-Norway, using stretches of the Eider River for the link between the two seas.

The Eiderkanal had been completed during the reign of Christian VII of Denmark in 1784 and was a forty-three-kilometer (twenty-seven mile) part of a one hundred and seventy-five-kilometer (one hundred and nine mile) long waterway from Kiel to the Eider River's mouth at Tönning on the west coast.

It is only twenty-nine meters (ninety-five feet) wide with a depth of three meters (ten feet), which limits the vessels that can use the canal to three hundred tonnes displacement.

During the nineteenth century, after Schleswig-Holstein had come under the government of Prussia (from 1871 the German Empire) following the Second Schleswig War in 1864, a combination of naval interests — the German navy wants to link its bases in the Baltic and the North Sea without the need to sail around Denmark—and commercial pressure encourage the development of a new canal.

A law establishing the Kiel Canal had been adopted on March 16, 1886.

In June 1887, construction works start at Holtenau, near Kiel.