Squannacook River

The Pleasant Street School is a historic school building on Pleasant Street in Ayer, Massachusetts. It is a 2+1⁄2-story Colonial Revival building, with a hip roof pierced by wide gabled dormers with bands of small windows. It was constructed in 1893 to a design by Boston architect Charles E. Parks and is one of the oldest school buildings in the town. It was enlarged in 1906, doubling it in size. It served as a public school until 1984.The building was listed on the National Register of Historic Places in 1986.

Ayer ( AIR) is a town in Middlesex County, Massachusetts, United States. Originally part of Groton, it was incorporated February 14, 1871, and became a major commercial railroad junction. The town was home to Camp Stevens, a training camp for Massachusetts volunteers during the American Civil War. Later, Fort Devens was established by the federal government to train New England soldiers for World War I. Fort Devens is a major influence on the area, although it is considerably smaller than when it was first closed in the mid-1990s. The town's population was 8,479 at the 2020 census.

Groton School (founded as Groton School for Boys) is a private college-preparatory boarding school located in Groton, Massachusetts. Ranked as one of the top five boarding high schools in the United States in Niche (2021–2022), it is affiliated with the Episcopalian tradition. Groton enrolls about 380 boys and girls, from the eighth through twelfth grades. It has one of the largest endowments of any prep school in the country at $477,000,000 as of June 30, 2021. Tuition, room and board, and required fees in 2014–2015 amounted to $56,700 (with books extra); 38% of the students receive financial aid.The school is a member of the Independent School League. There have been many famous Groton alumni in business and government, including U.S. President Franklin D. Roosevelt. For the 2020–2021 admissions cycle, Groton School reported an acceptance rate of 9%.

The Groton Leatherboard Company is a historic former factory complex at 6 W. Main Street in West Groton, Massachusetts. It manufactured leatherboard, a bonded leather made by pulping and compressing scrap leather, waste paper and wood pulp, but went out of business. The structure has since been renovated and adapted into senior housing called RiverCourt Residences. It was added to the National Register of Historic Places in 2002. The factory was built in 1916 on the site of an earlier saw and grist mill, which operated by waterpower from the Squannacook River. The original mill was established by the Tarbell family, a name prominent in Groton history since its settlement. The present complex's access road is flanked by brick houses built by brothers of that family; the Col. Abel Tarbell House is today a bed-and-breakfast, while the Asa Tarbell House is a mixed-use annex of the River Court senior housing facility. In 1862, artist Edmund C. Tarbell was born in the latter.

The Squanacook River Dam is just south of Groton Road between Groton and Shirley in Middlesex County, Massachusetts. It is one of five dams on the Squannacook River, which forms the boundary between Groton and Shirley.

Ayer station is an MBTA Commuter Rail station located off Main Street (Route 2A/111) in the Ayer Main Street Historic District of Ayer, Massachusetts. It serves the Fitchburg Line. There are three tracks through the station, two of which are served by a pair of low-level side platforms, which are not accessible. There is a shelter on the inbound platform. Ayer has been a major railroad interchange since the Fitchburg Railroad opened through South Groton in 1845, followed by the Stony Brook Railroad, Worcester and Nashua Railroad, and Peterborough and Shirley Railroad in 1848. The original depot was replaced with a union station with a large trainshed in 1848. Land speculation and industrial development spurred by the railroad access expanded the tiny farm village into the independent town of Ayer. A new station was constructed in 1896. By 1900, the town was served by five lines all controlled by the Boston and Maine Railroad, with service to Boston, Worcester, and Lowell plus New York, New Hampshire, and Maine. Passenger service ended on all of the lines except the Fitchburg mainline between 1931 and 1961. After a brief disruption in early 1965, the Massachusetts Bay Transportation Authority began subsidizing commuter rail service to Ayer as part of what would become the Fitchburg Line. The station and part of the line was closed in 1975, but reopened in 1980. CSX Transportation also runs freight trains through the town to various destinations. Planning began in 2003 for a parking structure to serve park-and-ride commuters at the station. After delays caused by disagreements with a property owner, the property to ensure a public access route to the station was acquired by the town in June 2016, allowing the parking expansion to proceed. The garage opened in 2019, with improvements to the station entrance constructed in 2020–21.

The Ayer Main Street Historic District encompasses most of the historic central business district of Ayer, Massachusetts. It extends along Main Street between Park and Columbia Streets, and was mostly developed between 1872 and 1898 as a hub of railroad and roadway-based economic activity. The district was listed on the National Register of Historic Places in 1989.

Ayer is a census-designated place (CDP) and the primary settlement in the town of Ayer in Middlesex County, Massachusetts, United States. The population of the CDP was 2,986 at the 2020 census, out of 8,479 in the entire town.

The Francis W. Parker Charter Essential School (usually referred to as the Parker Charter School by the public, or simply Parker by students) is a public charter school in Devens, Massachusetts, United States that serves students in grades 7 to 12. It was established in 1995 under the Massachusetts Education Reform Act of 1993, and serves about 400 students from 40 surrounding towns in north central Massachusetts, including Ayer, Shirley, Littleton, Leominster, Lunenburg, and Worcester. As a member of the Coalition of Essential Schools, a leading organization for education reform, Parker is known for its nontraditional educational philosophy. The school takes its name from Francis Wayland Parker, a 19th-century pioneer of the progressive school movement.

The Lovell General Hospital East is a former hospital at Fort Devens. It was named after the first Surgeon General of the United States Army, Joseph Lovell. After its closure, it was redeveloped into the United States Army Intelligence School.

Community Memorial Hospital is a historic hospital building at 15 Winthrop Avenue in Ayer, Massachusetts. The brick and stone Colonial Revival building was constructed in 1929, and expanded in the 1950s. It was designed by the Fitchburg architectural firm of Haynes & Mason, and was the first hospital building dedicated to serving the town of Ayer. The organization that operated the hospital was created by the merger of the Ayer Hospital Association, founded in 1912, and the Ayer Private Hospital, founded 1924. This organization operated the facility until 1957, when it was merged with the Groton Community Hospital. This group continued to operate the facility until 1971, when it moved to new premises and vacated this building.The building was listed on the National Register of Historic Places in 2004. The building is currently (2018) being operated as Nashoba Valley Assisted Living.

The Fort Devens Historic District is a historic district roughly bounded by El Caney St., Antietam St., Sherman Ave., MacArthur Ave. and Buena Vista Street in Devens, Massachusetts, encompassing territory in both Ayer and Harvard. The district is in a portion of the former Fort Devens and includes a large number of historically and architecturally significant buildings. The buildings that are deemed of most significant historic importance are those that were built in the period 1929-39. This building phase was begun after the United States Army decided to upgrade temporary facilities dating from World War I, to provide more permanent facilities at the base. This resulted in the construction of a significant number of Georgian Revival buildings in a rough U shape around a central parade ground. These buildings included dormitory facilities for soldiers, administrative office space, and warehouse facilities. This area is also significant as the site from 1933 to 1937 of an encampment of the Civilian Conservation Corps, and for its association with Congresswoman Edith Nourse Rogers, without whose efforts the base might have been closed instead of being upgraded.The district was added to the National Register of Historic Places in 1993. Its main boundaries on the north, west, and south, are Antietam and El Caney Streets. The eastern boundary is mainly Jackson Street, although there is an extension further eastward to Auman Avenue, where there are rows of single-family housing. One of the most visually dominant elements of the district are Rogers Field, the former parade ground, and the grouping of former barracks buildings on its north side.