A cool new interactive map online lets you see a bird’s eye view of Manhattan in 1609, the year Henry Hudson sailed into town.

Around the coops, you can see how Corlears’ Hook jutted out even more into the East River.

You can also see clearly why flood protection for the lower east side is so important — much of the land above present-day Delancey Street was low-lying floodplain, and where the ConEd facility is on 14th Street was actually offshore 400 years ago.