- Nashua is a city located in Hillsborough County, New Hampshire, United States. It is the second-largest city in the state, with a population of approximately 89,355 as of the 2020 census. Nashua is known for its vibrant downtown area, diverse cultural scene, and access to outdoor recreational activities. It is located along the Nashua River and is just a short drive away from Boston, Massachusetts. The economy of Nashua is driven by industries such as technology, manufacturing, healthcare, and professional services. The city is home to several parks, museums, theaters, and shopping centers, providing residents with plenty of entertainment options.