Diemitz lock, Navigation lock in Diemitz, Germany

Diemitz lock is a boat lock on the Müritz-Havel waterway at the Diemitz residential place, part of Mirow in the Mecklenburg Lake District. It was rebuilt in 1977–1978 and levels the water between the Labussee and the Großer Peetschsee, with an average drop of 1.29 metres. The chamber measures 42.1 metres by 5.34 metres and is closed by mitre gates.

The Diemitz lock was built in the 1880s to the Finow gauge dimensions on the Müritz-Havel waterway. Between 1977 and 1978 it was replaced by a new structure. It balances water levels between the Labussee and the Großen Peetschsee, with an average fall of 1.29 metres.

The lock is operated on site, and passenger and recreational boats may use it at set times from mid-March to the end of November. Since water tourism grew on the Mecklenburg Lake District, it has become the most frequented lock in the region, with nearly 40,000 recreational boats passing in 2015.

The lock is operated on site and can be used by passenger and recreational craft from mid-March to the end of November at set times. Waiting berths for sport boats have been expanded by the Wasserstraßen- und Schifffahrtsamt Oder-Havel. In 2015 it recorded just under 40,000 sport boat passages, the most of any lock in Germany.

The lock is part of a system of four interconnected lakes that allows boats to navigate through different water elevations across considerable distances. This network connects one of the largest continuous lake systems in the region and handles roughly 40,000 vessels annually.