Best SEO and internet marketing services in Schenectady County NY. Schenectady County zip codes - 12008, 12056, 12137, 12141, 12150, 12301, 12305, 12307, 12308, 12325, 12345 Schenectady County is a county in the U.S. state of New York. It is located in the east central part of the New York state. The county was founded in 1809. It was named from a Mohawk language word that means “on the other side of the pine lands”. The Schenectady County’s seat is the city of Schenectady. And it is the largest city in the county. The area of the county comprises 209 sq mi (that is 541 sq km). Land takes 205 sq mi (531 sq km) and water takes 4.9 sq mi (13 sq km). Only 2.3% of the territory is water. According to the census taken in 2010, the population of the county is 154,727 people. The density is 757/sq mi (292/ sq km). The Schenectady County Public Library (SCPL) is located in the county. It consists of a central library and eight branches. The Hudson River flows in the Schenectady County. And Mohawk River divides the county into two parts, but the county has the territory on both sides of the Mohawk River. This territory was originally occupied by the Mohawk people. Dutch colonists settled in the county in the 17th century. The village of Schenectady was founded in 1661.