All aboard the Voyageur II
This is the Voyageur II at dock in Grand Portage Bay. This boat circumnavigates the island, going from Grand Portage to Rock Harbor on Mondays, Wednesdays, and Fridays, and from Rock Harbor back to Grand Portage on Tuesdays, Thursdays, and Saturdays.
Sunday is apparently a day of rest -- or a day for picking up travelers stranded because of bad weather.