Dayville (CDP), Connecticut

The Dayville Historic District encompasses a collection of mid-19th century architecture in the Dayville village of Killingly, Connecticut. It is clustered around the junction of Main and Pleasant streets, extending along Main to High Street. The area flourished in the mid-19th century, as a consequence of the railroad being routed nearby, serving area textile mills. The district, residential except for a church, was added to the National Register of Historic Places in 1988.

Killingly High School is a public high school in Killingly, Connecticut. The school reported 792 students and 65 FTE classroom teachers for the 2014–2015 school year. Killingly High is the only public high school in the Killingly School District, which is on the eastern edge of Windham County. It also serves the nearby town of Brooklyn. For 2015, the community voted to make the school the sole polling place in Killingly. The Secretary of State informed the town registrar's office that this was a misinterpretation of statute, and in 2016, a second polling place was opened at the school's old location.Sports at the school are done as part of the Eastern Connecticut Conference.Killingly High was included in a segment of the reality TV series The Principal's Office in 2009.Old Killingly High School was built in 1908 and used by the school until 1965. The second building was then used until 2010 and continues to act as the site of an alternative learning program and the school district's central office. The first building was listed on the National Register of Historic Places in 1992 and is now the town's community center.

Quinebaug Valley Community College (QVCC) is a public community college in Danielson, Connecticut.

Harvard H. Ellis Technical High School, or Ellis Tech, is a technical high school located in Danielson, Connecticut. It is part of the Connecticut Technical Education and Career System. Founded in 1916 as the Putnam Trade School, it was the first technical school in Connecticut to have its own building. It is in the Connecticut Technical High School System. It receives students from many nearby towns.The current school building was constructed in 2014. The building underwent renovations to add 30,000 square feet of new floor space as well as a new gymnasium, a classroom wing, a media center, and a culinary arts program space.

The Five Mile River is a 23.5-mile-long (37.8 km) river located in Connecticut's northeast corner which flows through the towns of Thompson, Putnam, and Killingly. The original Nipmuc name was Assawaga, meaning "place between" or "halfway place". The Assawaga received its English name from the fact that the first land laid out upon it was "supposed to be about five miles from" Woodstock, Connecticut. The Five Mile is a tributary of the Quinebaug River and is part of the Thames River watershed. Its source is Little Pond (also known as Schoolhouse Pond), close to the Massachusetts border. It empties into the Quinebaug River at Danielson, near the intersection of Connecticut Route 12 and U.S. Route 6. The Five Mile River has several dams, most of which are remnants of defunct mills and some of which are still used by local industry. Its largest impoundment is Quaddick Reservoir. The best examples of surviving mill villages are Killingly in villages such as Pineville, Ballouville, Attawaugan, and Dayville.

The Old Westfield Cemetery is located at 320 North Street in the Danielson borough of Killingly, Connecticut. The cemetery was established in 1720, not long after Killingly's incorporation (1708). It occupies a 10-acre (4.0 ha) parcel on the north side of North Street, and is bounded in part by the Five Mile River. Its main entry is marked by granite pillars placed in 1920, giving access to a perimeter road. The cemetery is laid out in a form typical of 18th-century and early 19th-century, with graves lined up in relatively even rows, avoiding the mid-19th century rural cemetery movement. Most of its 450 graves date to the 19th century. The cemetery was listed on the National Register of Historic Places in 2010.Killingly was settled in 1707, when James Daniels purchased the area between the Quinebaug River and the Rhode Island border from James Fitch. Daniels is considered the founder of the village of Danielson, and is buried in this cemetery. It was laid out in 1728, and remained in continuous use until about 1900, when additional space on the south side of North Street was added. Most burials now take place in the modern southern parcel, although burials still take place in family plots in the old section. About 15% of the graves date to the 18th century, typically with slate stones carved with cherubs or winged soul effigies. The larger number of 19th-century burials have a wider variety of monuments, including the use of granite and marble. The most elaborate family monument is that of the Atwoods in the northeast quadrant, which features a Classical statue and drapery.

Danielson Airport (ICAO: KLZD, FAA LID: LZD, formerly 5B3) is a state-owned public-use airport located two nautical miles (4 km) northwest of the central business district of Danielson, a borough in the town of Killingly in Windham County, Connecticut, United States. The smallest airport in the state, it is included in the Federal Aviation Administration (FAA) National Plan of Integrated Airport Systems for 2017–2021, in which it is categorized as a local general aviation facility.Although most U.S. airports use the same three-letter location identifier for the FAA and IATA, this airport is assigned LZD by the FAA but has no assignment from the IATA.

Danielson is a borough in the town of Killingly in Windham County, Connecticut, United States. The population was 4,155 at the 2020 census.

Broad Street – Davis Park Historic District is a historic district in the borough of Danielson, in the town of Killingly, Connecticut. The district is mainly residential in character, and includes Davis Park, a 1.9-acre (0.77 ha) triangular park created in 1890 and bounded by Main, Reynolds, and Broad Streets. The district as a whole is 30 acres (12 ha) in size. It includes examples of Stick/Eastlake, Queen Anne, and Colonial Revival architectural styles and was added to the National Register of Historic Places in 1998. It includes 95 contributing buildings, one contributing site, and four contributing objects. The district is significant for its architecture, which includes many examples of Victorian architecture with rich detailing. The buildings in the district also reflect the institutions and people responsible with the development of Danielson. The town's growth began in 1809, when brothers James and Hezekiah Danielson built a cotton spinning mill. The house of Hezekiah, built about 1825, is the oldest building in the district. The village's growth was further fueled by other textile mills, the completion of the Norwich and Worcester Railroad through town in 1830, the establishment of other businesses, and the expansion of the textile mills from the 1850s onward. The houses in the Broad Street-Davis Park area were built by middle and upper-class residents, who chose the latest architectural styles and built large houses. The area also was above the river terrace, providing fine views and flood protection.: 12–13 It includes the Old Killingly High School building, which is separately listed on the National Register, and two churches: the 1891 Gothic St. Alban's Church, and the 1960s Baptist Church, the latter of which is not historically significant.

Killingly is a town in Windham County, Connecticut, United States. Killingly is the largest town by population in the Northeastern Connecticut Planning Region. The population was 17,752 at the 2020 census. It consists of the borough of Danielson and the villages of Attawaugan, Ballouville, Dayville, East Killingly, Rogers, and South Killingly.

The Danielson Main Street Historic District encompasses the historic late 19th-century commercial business district of the borough of Danielson in the town of Killingly, Connecticut. It extends along Main Street, between the Five Mile River and Spring Street, including a few buildings on adjacent side streets, representing the area's growth as a commercial and civic center in the late 19th and early 20th centuries. It was listed on the National Register of Historic Places in 1992.

The Old Killingly High School is a historic school building on 185 Broad Street in the Danielson section of Killingly, Connecticut. Built in 1908 and enlarged in 1927, it served as the town's high school until 1965, and then its junior high school until 1990. It is a significant local example of Renaissance and Colonial Revival architecture, designed by Hartwell, Richardson & Driver. It was listed on the National Register of Historic Places in 1992. It now houses the Killingly Police Department.