canal in the German state of Schleswig-Holstein
The Kiel Canal, the Nord-Ostsee-Kanal in German, formerly the Kaiser-Wilhelm-Kanal, connects the North Sea at Brunsbüttel to the Baltic Sea at Kiel through Schleswig-Holstein in northern Germany.
Completed in 1895, it is one of the world's busiest canals. Due to the personal insistence of Kaiser Wilhelm II, all crossings (ferry bridge or tunnel) are and continue to be free of charge for pedestrians.
The canal was built during the reign of the Navy-obsessed Wilhelm II to strengthen Germany's maritime warfare capabilities and allow it to move a fleet from Baltic to North Sea without Danish or other interference. One of the conditions of the Versailles Treaty that ended World War I was to open the Kiel Canal to international shipping, including military ships of nations with which Germany was at peace. As the former Hochseeflotte had sunk itself at Scapa Flow to avoid being turned over for use by the British, the Canal's military value for Germany approached zero after 1918. It has since become an important passageway for freight and more recently cruises. Even if you can't afford a ticket for one of the giants of the ocean, watching them pass by in the canal can be a fun activity. It is also used by pleasure craft.
The canal passes through relatively flat terrain and as the ships can't go all that fast (and have to wait in the locks or for passing ships) even moderately ambitious cyclists can accompany a ship for most or all of her trip through the Canal.
The canal enters the Baltic Sea near 🌍 Kiel. which as the capital and one of the two biggest cities of Schleswig Holstein shouldn't be hard to reach. In the west, the canal reaches the North Sea near 🌍 Brunsbüttel. which is a bit off non-nautical thoroughfares. The closest airport is in Hamburg (HAM)