It was the first lock reached on the new section of canal, and became the tidal limit on the navigation.
There are a series of fresh water lakes just past the tidal limit that are home to some of the most urban platypus in Australia.
The river's tidal limit is between 160 and 320 km from the sea.
From the tidal limit at Fordwich to the sea the river is fringed with marshes.
Until the 14th century Staines was the tidal limit, now downstream at Teddington.
The current tidal limit now extends 85 km upstream due to continual channel dredging.
Oath Lock marks the tidal limit of the River Parrett.
Strong winds, or the tidal limits may also affect the workings of a ferry crossing.
A significant find was discovered in 1998 between the high and low tidal limits off the north west coast of Norfolk at Holme-next-the-Sea.
For many years Yarm was at the tidal limit and head of navigation on the River Tees.