The Niagara Peninsula is an isthmus lying between the southwestern shore of Lake Ontario and the northeastern shore of Lake Erie, in Ontario, Canada. Technically an isthmus rather than a peninsula, it stretches from the Niagara River in the east to Hamilton, Ontario, in the west. The peninsula is located in the Golden Horseshoe region of Southern Ontario, and has a population of roughly 500 000 residents. The region directly across the Niagara River and Lake Erie in New York State is known as the Niagara Frontier.