Half of the world's population lives in coastal regions lapped by tidal waters. Yet how little most of us know about the tide.

With Aldersey-Williams as our guide to the most feared and celebrated tidal features on the planet, from the original maelstrøm in Scandinavia to the world's highest tides in Nova Scotia to the crumbling coast of East Anglia, the importance of the tide, and the way it has shaped - and will continue to shape - our civilization, becomes startlingly clear.