 So during the summer of 1608, John led an expedition of the Chesapeake Bay. So he's exploring its tributaries. He's looking for that Northwest Passage, going up every tributary, hoping it will go through. Along the way, he made a map, a map so detailed of the Chesapeake Bay that it was used for over 300 years. John was a very skilled mapmaker. In fact, he might have been known throughout history for his maps had he not done all of these other things.