Founded as a refuge for Catholics in 1634, Maryland was one of the original 13 colonies and played an important role in the Civil War as a border state. Maryland has 23 counties and 1 independent city (Baltimore).
10 Largest Counties in Maryland
1. Montgomery County
County Facts
- Population: 1,062,061 (2020 Census)
- Area Codes: 240, 301
- ZIP Codes: 20812-20997
- County Seat: Rockville
Geography and History
Montgomery County is located in the central region of Maryland, covering 507 square miles. It was established in 1776 and named after Richard Montgomery, a Revolutionary War general. Bordering Washington, D.C., Montgomery County has evolved from a primarily agricultural area into one of the most affluent and diverse regions in the country, with a strong focus on technology, government, and healthcare. Its proximity to the nation’s capital makes it a key location for federal agencies, contractors, and international organizations. The Potomac River forms the county’s western boundary, and the area is known for its mix of urban centers and suburban neighborhoods.
Colleges and Universities
- Montgomery College: A public community college with campuses in Rockville, Germantown, and Takoma Park, offering associate degrees, certifications, and workforce development programs.
- University of Maryland Global Campus (UMGC): A public university based in Adelphi but with a significant presence in Montgomery County, offering a wide range of online undergraduate and graduate degree programs.
- Johns Hopkins University (Montgomery County Campus): Offers graduate programs in biotechnology, cybersecurity, and education, primarily focused on working professionals.
- Washington Adventist University: A private Christian university located in Takoma Park, known for its programs in nursing, business, and the liberal arts.
Major Landmarks
Montgomery County is home to several major landmarks, including Great Falls Park, which offers stunning views of the Potomac River and waterfalls, and Glen Echo Park, a historic arts and cultural venue. The National Institutes of Health (NIH) and Walter Reed National Military Medical Center are both located in Bethesda, making the area a key hub for healthcare and biomedical research. The Strathmore Music Center in North Bethesda is a renowned venue for concerts and cultural events. Brookside Gardens in Wheaton is a beautiful public garden with themed sections and seasonal displays. The C&O Canal National Historical Park offers miles of hiking and biking trails along the historic canal. Downtown Silver Spring is a vibrant urban district with restaurants, shops, and entertainment.
2. Prince George’s County
County Facts
- Population: 967,201 (2020 Census)
- Area Codes: 240, 301
- ZIP Codes: 20601-20799
- County Seat: Upper Marlboro
Geography and History
Prince George’s County, located in central Maryland, spans 498 square miles. Established in 1696 and named after Prince George of Denmark, it has a long history tied to tobacco farming and early colonial settlement. Today, the county is a major suburban region surrounding Washington, D.C., and is home to several federal institutions, including NASA’s Goddard Space Flight Center and the National Archives at College Park. The county is diverse, with a significant African American population and a strong economy centered on government, education, and healthcare. Its geography includes the Anacostia River and the Patuxent River, which provide recreational opportunities.
Colleges and Universities
- University of Maryland, College Park (UMD): The flagship public university of the state, offering a wide range of undergraduate, graduate, and doctoral programs. UMD is known for its research programs in engineering, business, and the sciences.
- Bowie State University: A public historically Black university (HBCU) offering programs in education, business, and computer science.
- Prince George’s Community College: A community college offering associate degrees, certifications, and continuing education courses in a variety of fields.
- Capitol Technology University: A private institution in Laurel specializing in engineering, technology, and cybersecurity programs.
Major Landmarks
Prince George’s County is home to Six Flags America, a popular amusement park in Bowie, and National Harbor, a waterfront development that includes shops, restaurants, and the MGM National Harbor casino and hotel. FedExField, located in Landover, is the home stadium for the Washington Football Team. Greenbelt Park offers hiking, camping, and picnicking in a scenic forested area. Bladensburg Waterfront Park is a historic site along the Anacostia River, providing boat rentals and walking paths. The Surratt House Museum in Clinton tells the story of Mary Surratt, who was implicated in the conspiracy to assassinate President Abraham Lincoln.
3. Baltimore County
County Facts
- Population: 854,535 (2020 Census)
- Area Codes: 410, 443, 667
- ZIP Codes: 21013-21286
- County Seat: Towson
Geography and History
Baltimore County, located in northern Maryland, surrounds but does not include Baltimore City. Covering 682 square miles, the county was established in 1659 and has a rich history tied to agriculture, industry, and transportation. The county’s economy shifted from farming and mills to manufacturing during the 19th and 20th centuries. Today, it is one of the most populous counties in Maryland, with diverse suburban areas and significant economic activity in healthcare, education, and government services. The county’s geography includes rolling hills, forests, and a significant Chesapeake Bay shoreline.
Colleges and Universities
- Towson University: A public university and one of the largest in Maryland, known for its education, business, and nursing programs.
- Goucher College: A private liberal arts college in Towson offering undergraduate and graduate programs in arts, sciences, and humanities.
- Stevenson University: A private university with campuses in Owings Mills and Stevenson, offering programs in business, health sciences, and the liberal arts.
- Community College of Baltimore County (CCBC): Provides associate degrees, certifications, and workforce development programs across multiple campuses.
Major Landmarks
Baltimore County is home to the historic Hampton National Historic Site, an 18th-century Georgian mansion and estate. Gunpowder Falls State Park offers hiking, fishing, and kayaking along the Gunpowder River. Towson Town Center is one of the largest shopping malls in Maryland, attracting visitors from across the region. Oregon Ridge Park and Lodge offers trails, a nature center, and seasonal festivals. Fort Howard Park provides scenic views of the Chesapeake Bay and remnants of military fortifications from the Spanish-American War. Boordy Vineyards, located in Hydes, is one of Maryland’s oldest wineries, offering tours and tastings. Patapsco Valley State Park is a favorite destination for hiking and camping along the Patapsco River.
4. Baltimore City (Independent City)
County Facts
- Population: 585,708 (2020 Census)
- Area Codes: 410, 443, 667
- ZIP Codes: 21201-21298
- County Seat: N/A (Independent city)
Geography and History
Baltimore City is an independent city that serves as the largest city in Maryland and is located in the northern part of the state along the Chesapeake Bay. Founded in 1729, the city was an important port during the colonial era and played a significant role in the War of 1812, notably during the Battle of Baltimore, which inspired the writing of “The Star-Spangled Banner.” Baltimore later became a major center for shipbuilding, manufacturing, and railroads. Today, it is a city of contrasts, with revitalized neighborhoods alongside areas facing socioeconomic challenges. The city’s Inner Harbor is a key tourist and economic hub, and its history of innovation continues in industries like healthcare and education.
Colleges and Universities
- Johns Hopkins University: A world-renowned private research university known for its medical, public health, and engineering programs. The university’s medical campus is one of the top healthcare institutions in the world.
- University of Maryland, Baltimore (UMB): A public graduate school specializing in professional degrees in law, medicine, nursing, pharmacy, and dentistry.
- Loyola University Maryland: A private Jesuit university offering programs in business, education, and the liberal arts.
- Morgan State University: A public historically Black university (HBCU) known for its engineering, social work, and architecture programs.
- Maryland Institute College of Art (MICA): One of the top art and design schools in the U.S., offering undergraduate and graduate programs in visual arts.
Major Landmarks
Baltimore’s major landmarks include the Inner Harbor, which is home to attractions like the National Aquarium, Maryland Science Center, and historic ships such as the USS Constellation. Fort McHenry National Monument is famous for its role in the War of 1812. The Walters Art Museum and The Baltimore Museum of Art house significant collections of art spanning centuries. Oriole Park at Camden Yards and M&T Bank Stadium are the homes of the Baltimore Orioles and Ravens, respectively. Fells Point and Canton are historic waterfront neighborhoods known for their cobblestone streets and vibrant dining scenes. The Peabody Institute is a prestigious music conservatory located in the city.
5. Anne Arundel County
County Facts
- Population: 588,261 (2020 Census)
- Area Codes: 410, 443, 667
- ZIP Codes: 20711-21412
- County Seat: Annapolis
Geography and History
Anne Arundel County, located in central Maryland, covers 588 square miles along the Chesapeake Bay and its tributaries. Established in 1650, it was named after Anne Arundel, the wife of Cecil Calvert, 2nd Baron Baltimore. Annapolis, the county seat, serves as the capital of Maryland and has a rich colonial history, playing a significant role in the American Revolution. The county’s economy is driven by government and military institutions, including the U.S. Naval Academy and Fort George G. Meade. The proximity to the Chesapeake Bay also makes the county a center for maritime industries and recreation.
Colleges and Universities
- United States Naval Academy: A federal service academy located in Annapolis, offering a rigorous academic and military education to future Navy and Marine Corps officers.
- Anne Arundel Community College (AACC): A public community college in Arnold offering associate degrees and workforce development programs.
- St. John’s College: A private liberal arts college in Annapolis known for its Great Books curriculum, which focuses on classic works of Western literature, philosophy, and science.
- University of Maryland University College (UMUC): Although headquartered outside the county, it offers programs to students across Maryland, including those in Anne Arundel County.
Major Landmarks
Anne Arundel County’s landmarks include the U.S. Naval Academy, which offers public tours of its historic campus. Historic Annapolis is home to many colonial-era buildings, including the Maryland State House, the oldest state capitol still in continuous legislative use. Sandy Point State Park on the Chesapeake Bay provides opportunities for swimming, boating, and fishing. Quiet Waters Park in Annapolis offers walking trails, art galleries, and a dog beach. Fort George G. Meade, located near Odenton, is a major military installation and home to the National Security Agency (NSA). Thomas Point Shoal Light, a National Historic Landmark, is one of the few remaining screw-pile lighthouses in the Chesapeake Bay.
6. Howard County
County Facts
- Population: 328,200 (2020 Census)
- Area Codes: 410, 443, 667
- ZIP Codes: 20701-21797
- County Seat: Ellicott City
Geography and History
Howard County is located in central Maryland, covering 252 square miles. It was established in 1851 and named after John Eager Howard, a Revolutionary War hero and former governor of Maryland. The county’s economy has shifted from agriculture to a mix of technology, healthcare, and government services. Columbia, a planned community developed in the 1960s, has become a model for suburban growth and development, while historic Ellicott City retains much of its 19th-century charm. The county is known for its affluence, strong school system, and strategic location between Baltimore and Washington, D.C.
Colleges and Universities
- Howard Community College: A public community college located in Columbia offering associate degrees and workforce development programs in fields such as nursing, business, and cybersecurity.
- Johns Hopkins University (Applied Physics Laboratory): Located in Laurel, this research and development facility focuses on national security and space science, though it is not a degree-granting institution.
- University of Maryland Global Campus (UMGC): Provides online education to residents in Howard County and beyond, offering degrees in business, information technology, and cybersecurity.
Major Landmarks
Howard County’s landmarks include the historic Ellicott City Main Street, known for its antique shops, restaurants, and museums, including the B&O Ellicott City Station Museum, the oldest surviving railroad station in the U.S. Centennial Park offers scenic walking trails, fishing, and boating in Columbia. Merriweather Post Pavilion, an outdoor concert venue in Columbia, hosts major musical performances and events. The Robinson Nature Center provides interactive exhibits and programs about the environment. Patapsco Valley State Park, which stretches into Baltimore County, offers hiking, fishing, and historic ruins. Clark’s Elioak Farm in Ellicott City is a popular family-friendly attraction featuring a petting zoo and enchanted forest.
7. Harford County
County Facts
- Population: 260,924 (2020 Census)
- Area Codes: 410, 443, 667
- ZIP Codes: 21001-21160
- County Seat: Bel Air
Geography and History
Harford County is located in northeastern Maryland, covering 527 square miles along the Chesapeake Bay. Established in 1773, the county is named after Henry Harford, the last Proprietary Governor of Maryland. The county has a diverse landscape, including farmland, forests, and waterfront areas along the bay. The Susquehanna River forms its northern boundary, providing access to major shipping and trade routes. Harford County’s economy is driven by a mix of agriculture, manufacturing, and defense, with Aberdeen Proving Ground, a major U.S. Army facility, playing a central role.
Colleges and Universities
- Harford Community College: A public community college located in Bel Air offering associate degrees, certifications, and continuing education programs in fields such as healthcare, business, and trades.
- Towson University (Northeastern Maryland Campus): Offers degree completion programs in collaboration with Harford Community College, allowing students to pursue bachelor’s degrees locally.
Major Landmarks
Harford County is home to Aberdeen Proving Ground, a key military installation that conducts testing and research for the U.S. Army. Susquehanna State Park offers hiking, fishing, and camping along the Susquehanna River, as well as historic sites like the Rock Run Grist Mill. Havre de Grace is a charming waterfront town known for its maritime history, including the Havre de Grace Maritime Museum and the Concord Point Lighthouse, one of the oldest lighthouses on the East Coast. Ladew Topiary Gardens in Monkton features beautifully sculpted gardens and walking trails. The Liriodendron Mansion in Bel Air, a historic estate, hosts cultural events and art exhibitions.
8. Frederick County
County Facts
- Population: 271,717 (2020 Census)
- Area Codes: 240, 301
- ZIP Codes: 21701-21798
- County Seat: Frederick
Geography and History
Frederick County is located in western Maryland, covering 667 square miles, making it the largest county in the state by land area. Established in 1748, the county is named after Frederick Calvert, 6th Baron Baltimore. The area played a significant role during the Civil War, with several battles and historic sites located within the county. The fertile land in Frederick County has long supported agriculture, though the county has experienced significant suburban growth due to its proximity to Washington, D.C., and Baltimore. Its diverse economy includes manufacturing, agriculture, and technology.
Colleges and Universities
- Frederick Community College: A public community college offering associate degrees and workforce training programs in fields such as healthcare, business, and education.
- Hood College: A private liberal arts college in Frederick known for its programs in business, education, and biomedical science.
- Mount St. Mary’s University: Located in nearby Emmitsburg, this private Catholic university offers undergraduate and graduate programs in fields like education, business, and the humanities.
Major Landmarks
Frederick County is rich in history and natural beauty. Antietam National Battlefield, located just outside the county, is the site of one of the most significant battles of the Civil War. Monocacy National Battlefield offers a glimpse into another key Civil War battle. Cunningham Falls State Park is known for its waterfalls, hiking trails, and camping. Downtown Frederick is a vibrant historic district filled with shops, restaurants, and galleries, including the National Museum of Civil War Medicine. Catoctin Mountain Park, part of the Appalachian Mountains, is a popular destination for hiking and nature exploration. Mount St. Mary’s University and the National Shrine Grotto of Lourdes are also significant religious and educational landmarks in the area.
9. Charles County
County Facts
- Population: 166,617 (2020 Census)
- Area Codes: 240, 301
- ZIP Codes: 20601-20695
- County Seat: La Plata
Geography and History
Charles County is located in southern Maryland, covering 643 square miles along the Potomac River. Established in 1658, the county was named after Charles I of England. The county’s geography includes rivers, wetlands, and rolling farmland, with the Potomac River playing a crucial role in its early development as a transportation and trade route. Historically, tobacco farming dominated the economy, but today, Charles County has transitioned into a suburban region with a mix of residential, commercial, and industrial development, driven by its proximity to Washington, D.C.
Colleges and Universities
- College of Southern Maryland (CSM): A public community college with campuses in La Plata, Hughesville, and Leonardtown, offering associate degrees, certifications, and continuing education programs.
- University of Maryland Global Campus (UMGC): Provides online programs and continuing education opportunities to residents of Charles County.
Major Landmarks
Charles County is home to Port Tobacco Historic Village, once one of the busiest ports on the Potomac River and now a restored colonial village offering tours and exhibits. Piscataway Park, located along the Potomac River, offers beautiful views of Mount Vernon and is a popular spot for hiking and birdwatching. The Dr. Samuel Mudd House Museum in Waldorf tells the story of the doctor who treated John Wilkes Booth after President Lincoln’s assassination. Smallwood State Park offers boating, fishing, and camping, and features the restored home of General William Smallwood, a Revolutionary War hero. The county’s rivers and wetlands also provide excellent opportunities for kayaking and wildlife viewing.
10. Carroll County
County Facts
- Population: 172,891 (2020 Census)
- Area Codes: 410, 443, 667
- ZIP Codes: 21048-21787
- County Seat: Westminster
Geography and History
Carroll County is located in north-central Maryland, covering 449 square miles. Established in 1837, the county was named after Charles Carroll of Carrollton, a signer of the Declaration of Independence. The county’s landscape is characterized by rolling hills, farmland, and small towns. Historically, agriculture has been the dominant industry in Carroll County, with dairy farming and crop production playing a central role. Today, the county is a mix of rural and suburban areas, with many residents commuting to Baltimore or Washington, D.C., for work.
Colleges and Universities
- Carroll Community College: A public community college in Westminster offering associate degrees, workforce training, and continuing education programs.
- McDaniel College: A private liberal arts college in Westminster, known for its programs in education, psychology, and the social sciences.
Major Landmarks
Carroll County’s landmarks reflect its agricultural heritage and rural charm. The Union Mills Homestead is a preserved 19th-century estate and grist mill that offers tours and hosts events. Bear Branch Nature Center in Westminster provides environmental education and features hiking trails and a lake for fishing. Carroll County Farm Museum showcases the county’s agricultural history with exhibits, demonstrations, and an annual county fair. Piney Run Park offers boating, fishing, and hiking, along with a nature center. Hashawha Environmental Center provides outdoor education programs and hiking trails. Downtown Westminster is home to historic buildings, shops, and restaurants, as well as the Carroll Arts Center, which hosts performances and art exhibits.