The Newmarket Industrial and Commercial Historic District, located in Newmarket, New Hampshire, is a testament to the architectural and historical significance of the town's industrial and commercial development. This district is an embodiment of the rich heritage of a mill town that thrived in the heart of New Hampshire.

Encompassing 140 buildings and structures, the Newmarket Industrial and Commercial Historic District is a treasure trove of historical significance. At its core are the properties once owned by the Newmarket Manufacturing Company, which includes seven textile mills, a machine shop, an office building, storage structures, and an agent's house. In addition, the district features streets lined with multi-family housing units that were constructed to accommodate the company's workforce. The buildings in this district span from the early 19th century to the 1920s, reflecting the evolving landscape of Newmarket. Along the Lamprey River, the district boasts some 30 commercial structures primarily located along its Main Street, forming a north-south axis that runs parallel to the river.

The Newmarket Industrial and Commercial Historic District stands out as a unique example of a New England mill town that was developed as a cotton textile manufacturing community in the vein of the renowned Waltham-type mill towns. Unlike other mill towns from this era that were established by investors unaffiliated with the Boston Associates, who laid the foundation for Waltham and Lowell, the Newmarket Manufacturing Company, founded in 1822, continued to operate throughout the 19th century under the ownership and management of Salem, Massachusetts. The granite mills in the district, often described as the most beautiful textile factories of their time, are a distinctive feature and a rarity in coastal northern New England. These mills, made of granite, stand out as the best-preserved examples of this type, which was more commonly constructed using brick.

The historic and architectural significance of the Newmarket Industrial and Commercial Historic District was formally recognized when it was added to the National Register of Historic Places on December 1, 1980. Its reference number, 80000302, serves as a testament to its cultural and historical importance.

Today, visitors to Newmarket have the opportunity to admire the captivating architecture of the mills within this historic district. One of the best vantage points to view the Newmarket Mills is from the Heron Point Sanctuary. The sanctuary offers public parking for visitors, and you can access it by driving into the Lamprey River Trailer Park and following the signs to the sanctuary. The park is open to visitors from dawn to dusk, providing a picturesque glimpse into the rich history of Newmarket's industrial and commercial development.