At numerous times throughout the year, thousands of people gather along the banks of the River Severn in Gloucestershire to see one of the wonders of the natural world. A combination of geography and high tides coincide to create the Severn Bore, a rare phenomenon and one of only about sixty river bores in the world. Due to the huge difference in tides, and the funnelling effect of the ever-narrowing river, the incoming water is forced to become a tidal wave of up to two metres in height, travelling all the way upriver from the Severn Estuary to Gloucester itself. Chris Witts, who was working out on the river on the night of the fateful Severn Bridge disaster of 1960, is an acknowledged expert on the Severn Bore. Here he provides a clear and sprightly guide to this curious riverine occurrence, telling us when and where to best see the bore, why it happens, and who it affects and delights. On the journey we encounter fearless surfers, sunken ships, traditional fishermen, strange debris, and many a patient spectator, while a host of colour photographs vibrantly capture the Severn's bore and its beauty.