Fort Plain Historic District

US Post Office-Fort Plain is a historic post office building located at Fort Plain in Montgomery County, New York, United States. It was built in 1931, and is one of a number of post offices in New York State designed by the Office of the Supervising Architect of the Treasury Department under James A. Wetmore. It is a two-story, symmetrical brick building with a one-story rear wing in the Colonial Revival style. It features a shallow projecting frontispiece framed by four brick pilasters and a pair of Grecian style lamps with glass globes. It was listed on the National Register of Historic Places in 1989. It is located in the Fort Plain Historic District.

Fort Plain is a village in Montgomery County, New York, United States. As of the 2010 census, the village population was 2,322. The village is named after a fort built during the American Revolution at the junction of the Mohawk River and its tributary Otsquago Creek. The village of Fort Plain is at the border of the Towns of Minden and Canajoharie and is west of Amsterdam. Because of its small size and the close connections with neighboring communities, some former residents who now live in more populous regions use Fort Plain to refer collectively to the village of Fort Plain and the surrounding villages of Nelliston, and Palatine Bridge.

Otsquago Creek is a river that enters the Mohawk River in Fort Plain, New York. Otsquago is a Mohawk Indian word meaning 'under the bridge,' probably referring to an early bridge of felled trees along the creek, a way of making small bridges. It is also referred to as Otsquage on old maps, which is an Indian word for 'healing waters'. The source of the Otsquago Creek is about 12 miles southeast from its outlet, 1,360 feet above sea level and about 1,000 feet above the Mohawk River, in a marshy field by Van Hornesville, New York. Creamery Falls and Van Hornesville Falls are two waterfalls on the creek near Van Hornesville.

Nelliston Historic District is a national historic district located at Nelliston in Montgomery County, New York. It includes 56 contributing buildings. It encompasses three of Nelliston's residential streets developed between 1860 and 1890. It also includes the area along the railroad tracks containing two freight houses and the 1902 railroad station. Notable residential structures include the Abram Nellis Mansion; a brick two story Italianate style dwelling dated to the 1860s. It was listed on the National Register of Historic Places in 1980.

Lasher-Davis House is a historic home located at Nelliston in Montgomery County, New York. It was built in 1865 and is a small, 1+1⁄2-story frame building with a gable roof. It features an attractive porch with cut-out railings and brackets under the porch eaves. It was added to the National Register of Historic Places in 1980.

Nelliston is a village in Montgomery County, New York, United States. The population was 596 at the 2010 census. The name is from members of the Nellis family. The Village of Nelliston is in the Town of Palatine and is west of Amsterdam. The Erie Canal passes the village.

Nelliston School is a historic school building located at Nelliston, Montgomery County, New York. It was built in 1869 and is a two-story, square shaped brick institutional building. It has a shallow pitched gable roof. It served the educational needs of the community until 1971. It was added to the National Register of Historic Places in 2002. In 2022, the New Montgomery County childcare facility was put in the old Nelliston School building.

Walrath-Van Horne House is a historic home located at Nelliston in Montgomery County, New York. It was built in 1842 and was originally a 1+1⁄2-story Greek Revival stone house with a full-height portico. In 1895, a frame, shingled second story topped by a Mansard roof and new porch with mansard styling replaced the original. The house retains some Greek Revival interior styling, but the exterior has a Second Empire style. It was added to the National Register of Historic Places in 1980.

Waterman-Grampse House is a historic home located at Nelliston in Montgomery County, New York. It was built about 1865 and is a small, 1+1⁄2-story stone house of coursed rubble with cut-stone lintels and sills. A frame house built in the 1960s is attached to the north side. It was added to the National Register of Historic Places in 1980.

Jacob Nellis Farmhouse is a historic home located at Nelliston in Montgomery County, New York. It was built in the 1830s and is a rectangular, 1½-story, five-bay-long stone building with a three-bay lower 1½-story extension on the north side. The house is in the Greek Revival style. Also on the property is a small 19th-century barn and a large, multi-level 20th-century barn. It was added to the National Register of Historic Places in 1980.

Peter Ehle House is a historic home located at Nelliston in Montgomery County, New York. It was built about 1826 and is a rectangular, two story stone building with a gable roof and inside end chimneys in the Late Federal style. Also on the property is a large barn complex including a large frame barn, two carriage houses, and a small stone outbuilding. Remains of a large part stone barn are also present. It was added to the National Register of Historic Places in 1980.

Canajoharie (), also known as the "Upper Castle", was the name of one of two major towns of the Mohawk nation in 1738. The community stretched for a mile and a half along the southern bank of the Mohawk River, from a village known as Dekanohage westward to what is now Fort Plain, New York. The Mohawk Upper Castle Historic District has been designated as a National Historic Landmark and listed on the National Register of Historic Places. It contains the Indian Castle Church, built in 1769 for the Mohawk by Sir William Johnson, the British Superintendent of Indian Affairs, on land donated by his consort Molly Brant and her brother Joseph Brant, both leaders among the Mohawk. The site also has archeological resources related to Iroquois history. For a time the town was the home of the notable Mohawk leaders Hendrick Theyanoguin (1692–1755) and the Brants. According to Joseph Brant, Canajoharie means "a kettle stuck on a pole." A modern etymology translates it as "a washed kettle" or "the pot that washes itself". It refers to swirling actions of water in a large circular pothole in the Canajoharie Creek near where it empties into the Mohawk River. The modern village of Canajoharie, New York was settled by European Americans a few miles to the east of the historic Mohawk village.