So named in 1918 after Antoine Laumet de La Mothe, sieur de Cadillac, Donaquec et Monts Déserts, who once owned 400 square kilometres in Nouvelle-France that included Mount Desert Island. De La Mothe founded Fort Pontchartrain du Détroit, a settlement that eventually became a now bankrupt city in Michigan.
On 1 January 2011, the Admiral and the seaman hiked up the Mount, five days after the Christmas Blizzard of 2010.
Acadia National Park, crowned by the île des Monts Déserts. 2 August 2014.