The waters of the Bay are less than 10m deep and often below 5m. The Bay’s shallowness and funnel-like shape which concentrates the incoming tide into a smaller area, means the tides flow very fast. Incoming tides are often quoted as racing in “faster than a galloping horse.” You would not be able to outrun it. It has a very high tidal range of 10.53m – one of the highest tidal ranges in the world – and second highest in Britain, after the Bristol Channel.
The Arnside Bore is the tidal wave caused by the surge of the incoming tide meeting resistance from the sands and channels of the Bay. As the sun, moon, wind and rain can all affect the height and speed of the bore, it is impossible to predict when it will be at its most spectacular.
To have a chance of seeing the Bore at Arnside, aim to be on Arnside Promenade 1.5-2 hours before high water.
Check the tide times here
The Arnside siren is a seasonal warning alarm used to alert people to the incoming tide.
It sounds very similar to a World War II air raid siren and can be heard from miles around.
The siren operates from Easter to the end of October, and sounds twice before daylight high-tide.
The first sounds 30 minutes before the tide is due to come in, the second sounds as the tide is actually coming in.
Find out more about staying safe on the coast