Harford County is located in the U.S. state of Maryland. As of the 2020 census, the population was 260,924. Its county seat is Bel Air. Harford County is included in the Baltimore-Columbia-Towson, MD Metropolitan Statistical Area, which is also included in the Washington-Baltimore-Arlington, DC-MD-VA-WV-PA Combined Statistical Area.
The town of Bel Air is the county seat of Harford County, Maryland. According to the 2020 United States census, the population of the town was 10,661.
Bel Air North is a census-designated place (CDP) in Harford County, Maryland, United States. It is situated immediately north of the incorporated town of Bel Air. As of the 2010 census, the CDP population was 30,568, up from 25,798 in 2000.
Bel Air South is a census-designated place (CDP) in Harford County, Maryland, United States. The population was 47,709 at the 2010 census, up from 39,711 in 2000.
Edgewood is an unincorporated community and census-designated place (CDP) in Harford County, Maryland, United States. The population was 25,562 at the 2010 census, up from 23,378 in 2000.
Fallston is a census-designated place (CDP) in Harford County, Maryland, United States. The population was 8,958 at the 2010 census, up from 8,427 in 2000. Fallston is a semi-rural community consisting mostly of farms and suburban-like developments.
Jarrettsville is an unincorporated community and census-designated place (CDP) in Harford County, Maryland, United States. The population was 2,888 at the 2020 census.
Perryman is an unincorporated community and census-designated place (CDP) in Harford County, Maryland, United States. The population was 2,342 at the 2010 census.
Pleasant Hills is a census-designated place (CDP) in Harford County, Maryland, United States. The population was 3,379 at the 2010 census, up from 2,851 in 2000. There is no post office with the designation "Pleasant Hills"; most of the residents have either Fallston or Kingsville addresses and consider themselves as belonging to those communities.
Riverside is a census-designated place (CDP) in Harford County, Maryland, United States. The population was 6,425 at the 2010 census. The term "Riverside" is generally used interchangeably with "Belcamp"; both names are accepted for the U.S. Postal Service's ZIP Code of 21017. However, the original community of Belcamp is located south of U.S. Route 40, outside the Riverside CDP.
Seabrook is an unincorporated community and census-designated place (CDP) in Prince George's County, Maryland, United States, located approximately 12 miles (19 km) east of Washington, D.C. Per the 2020 census, the population was 19,627. Prior to 2010, Seabrook was part of the Lanham-Seabrook census-designated place.
Darlington is an unincorporated community and census-designated place in northeastern Harford County, Maryland, United States. The population was 409 at the 2010 census. The center of the community was listed on the National Register of Historic Places as the Darlington Historic District in 1987. Median household income is $66,563. The percentage of people in poverty is 5.3%.
Maryland Route 23 is a state highway in the U.S. state of Maryland. The state highway runs 20.58 miles (33.12 km) from U.S. Route 1 in Hickory north and west to the Pennsylvania state line near Norrisville, where the highway continues as Pennsylvania Route 24. MD 23 is an L-shaped highway in northwestern Harford County that consists of two major sections. Between US 1 and MD 165 in Jarrettsville, MD 23 is marked east–west along a two-lane road with partial control of access named East–West Highway. From MD 165 to the state line, the state highway is marked north–south along Norrisville Road, a rural two-lane highway that passes through the villages of Madonna and Shawsville. The two sections of MD 23 are connected by a short concurrency with MD 165.
Maryland Route 165 is a state highway in the U.S. state of Maryland. The state highway runs 20.38 miles (32.80 km) from Baldwin north to the Pennsylvania state line in Cardiff, where the highway continues as Pennsylvania Route 74. MD 165 passes through western and northern Harford County, where it connects the communities of Fallston, Jarrettsville, Pylesville, and Whiteford. The state highway was constructed as part of MD 24 through Pylesville and Whiteford in the late 1910s and early 1920s. MD 165 from Baldwin through Jarrettsville to west of Pylesville was built in the late 1920s and early 1930s. When MD 24 was rerouted in 1933, MD 165 was extended along that highway's old routing through Pylesville and Whiteford, much of which was relocated in 1960.
Maryland Route 24 (MD 24) is a state highway in the U.S. state of Maryland. The state highway runs 25.17 miles (40.51 km) from an entrance to Aberdeen Proving Ground in Edgewood north to the Pennsylvania state line near Fawn Grove, Pennsylvania, where the road becomes State Route 2055 (SR 2055). MD 24 is the main north–south highway of Harford County. The southern half of the state highway connects U.S. Route 1 (US 1) and the county seat of Bel Air with Aberdeen Proving Ground, US 40, and Interstate 95 (I-95) through a suburban corridor. The northern half of MD 24 is a rural highway that passes through Rocks State Park.
Maryland Route 543 is a state highway in the U.S. state of Maryland. The state highway runs 19.08 miles (30.71 km) from U.S. Route 40 in Riverside north to MD 165 in Pylesville. MD 543 is a north–south highway through central Harford County that connects the communities of Creswell, Fountain Green, Hickory, and Ady with the county's four main east–west highways: US 40, Interstate 95 (I-95), MD 22, and US 1. MD 543 was originally constructed in the early 1930s from Hickory to north of Ady, where the highway followed part of what is now MD 646. The state highway swapped routes with MD 646 to end in Pylesville by 1946. MD 543 was extended south in three steps to MD 7 in the 1950s. The state highway was rerouted at its southern end when I-95 was constructed in the early 1960s and again when the highway's interchange with the Interstate was built in the early 1990s. MD 543 was extended south through Riverside to US 40 in the mid 1990s.
Maryland Route 136 is a state highway in the U.S. state of Maryland. The state highway runs 30.04 miles (48.34 km) from MD 7 near Abingdon north to MD 23 in Norrisville. MD 136 is an L-shaped route that connects the communities of Creswell, Churchville, Dublin, and Whiteford in eastern Harford County with each other and with Norrisville in the county's northwestern corner. The state highway is connected to the cities of Aberdeen and Havre de Grace via its connection with MD 22. MD 136 is also linked to the county seat of Bel Air from the east through MD 22, from the northeast by U.S. Route 1, from the north via MD 24, and from the northwest by MD 23. The state highway starts on the coastal plain near the Chesapeake Bay and crosses Harford County's two main tributaries of the Susquehanna River, Deer Creek and Broad Creek, while traversing a wide swath of the Piedmont. MD 136 is the second longest Maryland state highway entirely within one county after MD 235.
Forest Hill is an unincorporated community in Harford County, Maryland, United States, located north of the county seat of Bel Air. The main part of town is located at the intersection of Maryland Route 24 and Jarrettsville Road. Until 1958, this community was served by the Maryland and Pennsylvania Railroad at milepost 30.3.
Libertytown is an unincorporated community and census-designated place (CDP) in Frederick County, in the U.S. state of Maryland. As of the 2010 census it had a population of 950. The Abraham Jones House was listed on the National Register of Historic Places in 1973.
Spring Ridge is census-designated place (CDP) and suburban housing community in Frederick County, in the U.S. state of Maryland, just outside the city of Frederick. As of the 2020 census it had a population of 6,005. Before 2010, it was part of the Linganore-Bartonsville, Maryland census-designated place, which was split into three for the 2010 census.
