The Bay of Mont Saint-Michel experiences the highest tides in continental Europe, with up to 15-meter difference between high and low tide. This amazing natural phenomenon completely transforms the landscape: at high tide, the island is entirely surrounded by water, while at low tide vast expanses of sand and mud are exposed. Guided bay walks are available at low tide, but are dangerous without a guide due to quicksand and the rapidly rising water. The tide comes in as fast as a galloping horse!