Hello; Elbląg Canal is a canal in Poland, in Warmian-Masurian Voivodeship, 80.5 kilometres (50.0 mi) in length, which runs southward from Lake Drużno (connected by the river Elbląg to the Vistula Lagoon), to the river Drwęca and lake Jeziorak. It can accommodate small vessels up to 50 tonnes (49 long tons; 55 short tons) displacement. The difference in water levels approaches 100 metres (330 ft), and is overcome using locks and a system of inclined planes between lakes. Today it is used mainly for recreational purposes. It is considered one of the most significant monuments related to the history of technology and was named one of the Seven Wonders of Poland. The canal was also named one of Poland's official national Historic Monuments (Pomnik historii), as designated January 28, 2011. Even though I am being a Master Mariner - I am amazed at this wonderful idea. This technology is also used in Docking small ships whereas similar system used called 'Slip ways'.