What Every Block of Manhattan Looked Like 400 Years Ago

When Henry Hudson arrived in 1609, the island called Manahatta was a lush area with hills, swamps, beaches, forests, rivers, meadows, tidal flats, and a wide variety of plant and animal life. Landscape ecologist Dr. Eric Sanderson launched a project to detail what every block of the city was like back then. He’s worked on it since 1999, and now you can use the interactive map from the Welikia Project to see it yourself. The research that went into the work is staggering.

The 16-year process of uncovering what once lay beneath the super-dense urban fabric was (and is) a feat of incredibly detailed historical detective work. The geological and landscape data was the simplest–it came from a 1782 map drawn by the British that included locations of more than 60 miles of streams, as well as 300 natural springs and plenty of wetlands, beaches, and hundreds of types of trees, plants and soil types. Not to mention dozens of hills–after all, the island’s name is derived from the Lenape word Mannahatta, or “the island of many hills.”
But figuring out the specifics of the city’s more than 50 ecological groups was more difficult, as Sanderson explains on the project’s website. They created a list of species that lived on the island, then compared them against the existing data about different environment pockets in the island, creating a web of relationships based on which species were more likely to flourish or depend on which ecologies – they call this a Muir web, after the naturalist John Muir, who popularized this idea of interconnected habitats. The data visualization designer Chris Harrison created this Muir web of the associations between known habitats and species in Manhattan in the 17th century:

The Welikia Project is far from finished- they hope to eventually have all five boroughs of New York City mapped this way. The rest will be more difficult, as they weren’t mapped as early as Manhattan. Read more about the project at Gizmodo.