It is one of Britain’s few truly spectacular natural phenomena. It is a large surge wave that can be seen in the estuary of the River Severn, where the tidal range is the 2nd highest in the world, being as much as 50 feet.  It forms upstream of Sharpness and can be seen as far upstream as Maisemore. As well as the sight and sound of the natural phenomen added excitement is created by the people who get in the river to surf the bore.