As of 2010, the city had a population of 36,047. ZIP code 19901 is located in central Delaware and covers a slightly less than average land area compared to other ZIP codes in the United States. The people living in ZIP code 19901 are primarily white. View listing photos, review sales history, and use our detailed real estate filters to find the perfect place. The percentage of children under 18 living in the 19901 Z… It also has a slightly less than average population density. It was named by William Penn for Dover in Kent, England. It is also the county seat of Kent County, and the principal city of the Dover, DE Metropolitan Statistical Area, which encompasses all of Kent County and is part of the Philadelphia-Wilmington-Camden, PA-NJ-DE-MD Combined Statistical Area. It is located on the St. Jones River in the Delaware River coastal plain. Notable locations in zip code 19901: Wesley College Parking Lot D (A), Little River Range Lights (B), Tudor Industrial Park (C), MCD Business Park (D), Dover East Industrial Park (E), Dover Downs (F), Leipsic River Range Lights (G), Transportation Administration Center (H), Leipsic Volunteer Fire Company Incorporated (I), Dover Air Force Base Fire Department (J), Kent County Sheriff's Department (K), William C Jason … There are also a large number of single parents and a small number of families. The number of young adults is extremely large while the number of people in their late 20s to early 40s is extremely large. Dover is the capital and second-largest city in the U.S. state of Delaware. Zillow has 116 homes for sale in 19901.