Prologue
On January 25 2012, Swedish salvage divers discovered an unexplained object resting at the bottom of the Baltic Sea. Sonar readings indicated the mysterious object was 180 feet across. A second, smaller object of similar proportions was detected nearby. The presence of 400 foot long "drag marks" behind the objects indicated they weren't sunken ships.
Create an underwater map that reveals these mysterious objects on the sea floor.