Columbia is an unincorporated community and census-designated place (CDP)[10] located within Knowlton Township in Warren County, in the U.S. state of New Jersey.

While the community has existed for over a century, the CDP was created as part of the 2010 United States Census.

[14] The area is served as United States Postal Service ZIP Code 07832.

It was removed in 2018 to provide safe fish passage and improve the river and stream habitat.

[1][2] The 2010 United States census counted 229 people, 77 households, and 55 families in the CDP.