The Gezeitenwehr Kronstadt (Tidal Weir of Kronstadt) refers to a significant structure in Kronstadt, a historic town located on Kotlin Island near St. Petersburg, Russia. The term "Gezeitenwehr" translates to "tidal weir" or "tidal barrage," indicating its function related to the control of tidal waters in the area.

The Kronstadt Tidal Weir was part of an ambitious project in the late 19th century designed to protect the port and naval base of Kronstadt from the destructive effects of tidal changes, especially from storm surges. The weir acted as a barrier that controlled the water level, allowing for more predictable and safer navigation for ships entering or leaving the port.

Kronstadt, as a strategic naval base, played a critical role in the defense of St. Petersburg and the broader Russian Empire. The tidal barrage was essential in ensuring the stability and accessibility of the harbor, which was crucial for the Russian Navy. It is a remarkable example of engineering designed to protect important infrastructure in the face of natural forces.

This system contributed significantly to the economic and military importance of the region and remains an important feature of the area’s historical maritime engineering legacy.