Geography of Hillsborough County, New Hampshire

By | March 5, 2024

Geography of Hillsborough County, New Hampshire

Hillsborough County, nestled in southern New Hampshire, is a region characterized by a diverse and picturesque landscape, encompassing rolling hills, fertile valleys, and historic rivers. This comprehensive overview will delve into the topography, climate, rivers, lakes, and other geographical elements that contribute to the unique character of Hillsborough County.


According to Simplyyellowpages, Hillsborough County’s topography is defined by a mix of hills, valleys, and plains. The county is part of the larger New England Upland, a region known for its varied topography and scenic beauty. Elevations in Hillsborough County range from around 200 feet above sea level in low-lying areas to over 1,000 feet in the elevated regions, creating a diverse and visually appealing landscape.

The county is home to the Wapack Range, a series of hills and small mountains that offer panoramic views of the surrounding countryside. Additionally, the Souhegan and Merrimack River valleys contribute to the county’s varied topography, providing fertile land for agriculture and settlements.


Hillsborough County experiences a humid continental climate, characterized by four distinct seasons with warm summers and cold winters. The region’s climate is influenced by its inland location, away from the moderating effects of coastal waters. This results in temperature variations throughout the year.

Summers in Hillsborough County are generally warm, with average daytime highs ranging from the 70s to the 80s°F (21 to 32°C). Winters can be cold, with average daytime highs in the 20s and 30s°F (-6 to 4°C). The county receives an average annual precipitation of around 40 inches, with rainfall distributed relatively evenly throughout the year.

The seasonal changes contribute to the vibrant display of fall foliage, a hallmark of New England autumns, adding to the region’s scenic allure.

Rivers and Lakes:

Hillsborough County is crisscrossed by several rivers and dotted with lakes, contributing to both its natural beauty and historical significance. The Merrimack River, one of the longest rivers in New England, flows through the eastern part of the county. This vital waterway has played a crucial role in the region’s development, providing transportation and supporting early industries.

The Souhegan River, a tributary of the Merrimack, meanders through the county, enriching the surrounding landscapes and offering opportunities for recreation and scenic enjoyment. Numerous smaller rivers and streams, such as the Contoocook River, contribute to the county’s hydrology, creating a network of watercourses that shape the land.

While natural lakes are not as prevalent in Hillsborough County compared to other regions, there are several ponds and reservoirs, often used for recreation and water supply. Examples include Gregg Lake and Baboosic Lake, each adding to the county’s diversity of water resources.

Vegetation and Wildlife:

Hillsborough County’s vegetation is characterized by a mix of deciduous and coniferous forests, open fields, and agricultural lands. The county’s woodlands are home to a variety of tree species, including oak, maple, pine, and hemlock. The forests provide habitats for diverse flora and fauna, contributing to the region’s biodiversity.

The agricultural landscape of Hillsborough County includes a variety of crops, such as apples, corn, and pumpkins. The fertile valleys and plains support farming activities, contributing to the county’s agricultural heritage.

Wildlife in the region includes white-tailed deer, turkeys, songbirds, and a variety of small mammals. The rivers and water bodies are habitats for fish and waterfowl, enriching the ecological diversity of the county.

Geological Features:

Hillsborough County’s geological features reflect its complex geological history, shaped by glacial processes and ancient rock formations. The presence of drumlins, small hills shaped by glacial action, is evident in parts of the county. Glacial deposits, including moraines and eskers, contribute to the diverse topography.

The Wapack Range, with its rocky outcrops and scenic overlooks, showcases the geological diversity of the region. The Souhegan and Merrimack River valleys, carved by glacial meltwater, add to the county’s geological tapestry.

The underlying bedrock includes a mix of sedimentary, metamorphic, and igneous formations, providing a foundation for the diverse landscapes found in Hillsborough County.

Human Impact and Activities:

Hillsborough County has been significantly shaped by human activities, from early settlements and agriculture to industrialization and modern urbanization. The Merrimack River, historically harnessed for water-powered mills and factories, played a crucial role in the county’s industrial development during the 19th century.

The county’s agricultural heritage continues to be a significant aspect of its identity. Farms and orchards contribute to the local economy, and agritourism activities, such as apple picking and farm tours, attract visitors to experience rural life.

Urban and suburban areas, including the city of Manchester and the town of Nashua, showcase the county’s modern development. These centers serve as hubs for commerce, education, and cultural activities, reflecting the dynamic interplay between human settlement and the natural environment.

Outdoor recreation is a key aspect of life in Hillsborough County, with residents and visitors enjoying activities such as hiking, fishing, and boating. Parks and conservation areas, including the Wapack National Wildlife Refuge and Greenfield State Park, provide opportunities for nature exploration and relaxation.

Cultural and Historical Sites:

Hillsborough County is rich in cultural and historical sites that offer glimpses into its past. The city of Nashua, with its historic mill buildings and Victorian architecture, reflects the industrial heritage of the region. The Millyard Museum in Manchester preserves the history of the Amoskeag Manufacturing Company, once a major textile manufacturer.

The town of Peterborough, located in the Monadnock Region, boasts a charming downtown and cultural institutions such as the Peterborough Players Theater, contributing to the county’s artistic and literary heritage.

Historic homes, including the Franklin Pierce Homestead in Hillsborough and the home of poet Robert Frost in Derry, provide insights into the lives of notable figures in American history and literature.


Hillsborough County, New Hampshire, is a region where natural beauty and human history intertwine to create a diverse and vibrant landscape. From the hills and valleys sculpted by glacial forces to the dynamic urban centers and historic sites, the county reflects the enduring connection between the people and the land. As Hillsborough County continues to evolve, balancing modern development with the preservation of its natural and historical assets will be crucial for ensuring a sustainable and harmonious future for this dynamic New England region.