With about 25,000 visitors annually and no roads or electricity, Isle Royale's seclusion is both its appeal and what makes recent deaths there so mysterious.

Earlier this week, the National Park Service reported that two campers were found dead at a remote backcountry campground on Isle Royale — an island on Lake Superior that is a two-hour ferry ride from Grand Portage,

The Federal Bureau of Investigation in Detroit confirmed June 11 that federal officials were at the Isle Royale National Park, following the death of two campers at the remote campground.