This 4.2km/2,7mi-long submersible causeway, in use since the 18C, was the only way for vehicles to reach the island from the late 19C up until 1971, when the toll bridge was opened. Mostly frequented by local oyster and mussel farmers nowadays, the Gois is an absolutely unique place that is not to be missed. Floats are provided along the way so that should you be caught by the rapidly rising waters, you can pull yourself to safety and wait for the tide to turn.