Geneva is a city in Ontario and Seneca counties in the U.S. state of New York. It is located at the northern end of Seneca Lake; all land portions of the city are within Ontario County; the water portions are in Seneca County. The population was 13,261 at the 2010 census. The city is supposedly named after the city and canton of Geneva in Switzerland. Others believe the name came from the word "Seneca". The main settlement of the Seneca was spelled Zoneshio by early white settlers, and was described as being 2 miles north of Seneca Lake.