Between Granville and Cancale, this depression of about 193 sq. miles (500 km²) is where the biggest tides in Europe take place. Either at low tide or when the high tide is at its peak, the bay of Mont Saint-Michel reveals all its secrets: the fauna, the flora, the light, and the reflections of the sky over the sea... Seen from the coast, the bay looks like a vast flat expanse. But that is an illusion! In fact, three coastal rivers – the ‘Sée’, the ‘Sélune’ and the ‘Couesnon’ – flow through the bay, creating new channels every day that isolate sandbanks. When the tide rises, the water flows through these channels, encircling the mounds of sand before submerging them.