Trent Aegir

At certain times of the year, the lower tidal reaches of the Trent experience a moderately large bore (up to five feet (1.5m) high).

[1] The funnel shape of the river mouth exaggerates this effect, causing a large wave to travel upstream as far as Gainsborough, Lincolnshire, and sometimes beyond.

[5] A private prediction of the Aegir is regularly updated on an informational site about the neighbouring community of Crowle, Lincolnshire.

[6] It is alleged that King Cnut performed his purposely unsuccessful attempt to turn the tide back in the River Trent at Gainsborough.

The huge rolling waves then dashed the shipping from their moorings, if they were not well-moored and managed; and boats were often crushed to pieces.