What's the most densely populated place in the US?

Q: What is the most densely populated place in the United Sates?

A: The incorporated place with the highest density in the country is Guttenberg, a town in Hudson County, New Jersey. Only four blocks wide, the town has a population of 10,807.

Guttenberg is a bedroom community with about a third of its employed residents working in New York City. The town has twice the density of New York City.