A broken lock chamber in Germany’s Kiel Canal is causing chaos to shipping, including cruise ship transits.

The 98 kilometer (60 mile) canal, linking the Baltic to the North Sea, is the world’s busiest artificial waterway and is used by ships to avoid sailing all the way around the coast of Denmark.

One of the four lock chambers on the eastbound lane became unusable on Sunday when the carriage supporting one of the gates derailed from its slide rail, according to industry web site Seatrade Insider.