Thames

The Thames widens into a tidal estuary between the shores of Essex and Kent before opening into the North Sea. Its channels carry vessels toward London and the mouth of the Medway, but the shallows and sandbanks make the approach hazardous. Among them is the Nore, a bank near the entrance to the Medway. In 1732 a lightship was placed there to guide vessels entering the Thames and Medway, marking a danger on a waterway crowded with ships bound for the capital and its ports.