In September 1609, the beach near the tip of the island was surrounded by thickly wooded hills. Passenger pigeons flew overhead; porpoises hunted in the harbor. Around 600 Native Americans lived on the island. And they were the ones who, on Sept. 12, must have watched as a European, Henry Hudson, guided his small wooden ship into the Muhheakantuck (later Hudson’s) River, cleaving the waters with the narrow prow of history that would one day create New York City in its wake.
To the native Lenape people, whom Hudson met and traded with, Mannahatta meant “island of many hills.” Modern ecological research has shown that Mannahatta was an island of remarkable biological diversity. Its 55 ecosystems encompassed stately forests, rich wetlands, sandy beaches and rocky shores, eel grass meadows and deep marine waters. This 25-square-mile island had 66 miles of streams and more ecosystems per acre than Yellowstone; more plant species than Yosemite; and more birds than the Great Smoky Mountains National Park does today.
Comment: Having lived in Manhattan for about 6 months (back in 1974), it's hard to imagine!