Mont-Saint-Michel (môN-săN-mēshĕlˈ) [key], rocky isle (1993 est. pop. 72) in the Gulf of Saint-Malo, an arm of the English Channel, Manche dept., NW France, 1 mi (1.6 km) off the coast, near Avranches. The isle is linked with the mainland by a causeway (built 1875), but was long only accessible by land at low tide. By 2006, however, the silting of the surrounding waters caused Mont-Saint-Michel to be truly an island only at extreme high tides, but a plan to reverse the silting is being implemented. The celebrated Benedictine abbey of Mont-Saint-Michel was founded in 708 by Saint Aubert, bishop of Avranches. A gigantic group of buildings, rising three stories high, serves, with the summit of the cone-shaped rock, as a base for the great abbey church. Six of these structures on the side facing the sea form the unit called La Merveille [the marvel], constructed from 1203 to 1228. Mont-Saint-Michel is one of the most imposing achievements of Gothic architecture. Strongly fortified, the abbey was frequently assaulted by the English in the Hundred Years War but was never captured. It remains one of the major tourist attractions of Europe. Henry Adams wrote of it with feeling in Mont-Saint-Michel and Chartres.