Roxbury is a township in southwestern Morris County, in the U.S. state of New Jersey. As of the 2020 United States census, the township's population was 22,950, a decrease of 374 from the 2010 census count of 23,324, which in turn reflected a decline of 559 from the 23,883 counted in the 2000 census. The township is located approximately 36 miles we…Roxbury is a township in southwestern Morris County, in the U.S. state of New Jersey. As of the 2020 United States census, the township's population was 22,950, a decrease of 374 from the 2010 census count of 23,324, which in turn reflected a decline of 559 from the 23,883 counted in the 2000 census. The township is located approximately 36 miles west-northwest of New York City, 27 miles west-northwest of Newark, New Jersey and 26 miles east of the Delaware Water Gap on the border of New Jersey and Pennsylvania.