People living on the low-lying shores of the Bristol Channel and Severn estuary began their day like any other on January 30 1607. The weather was calm. The sky was bright.
Then, suddenly, the sea rose without warning. Water came racing inland, tearing across fields and villages, sweeping away the homes, livestock and people in its path.
By the end of the day, thousands of acres were underwater. As many as 2,000 people may have died. It was, quite possibly, the deadliest sudden natural disaster to hit Britain in 500 years.