Harlem

My first mistake here is that Harlem is not a full-fledged borough, it’s just a neighborhood in Manhattan. It’s the upper boundary of Manhattan, north of 110th Street, which is the top boundary of Central Park.

It extends north to the Harlem river, which cuts diagonally from northwest to southeast. This river is what makes Manhattan an actual island. The other side of the river is the mainland, continental US. Across the river is The Bronx.

So, it’s easy to say, “Harlem is everything between the north end of the park and the end of the island.”

However, that’s not quite true.

• Washington Heights can be considered north of Harlem (north of 155th), but south of the river. It sits along the Hudson on the west side. Fort George is a “sub-neighborhood” inside Washington Heights.
• Inwood is a smaller neighborhood just north of Washington Heights which borders the river. The streets aren’t numbered, and they turn diagonally, so there’s not a clear street border.
• The area north and east of the park is technically East Harlem.