Niagara Peninsula in the context of "Niagara Falls, Ontario"

The Golden Horseshoe (French: Fer à cheval doré) is a secondary region of Southern Ontario, Canada, which lies at the western end of Lake Ontario, with outer boundaries stretching south to Lake Erie and north to Lake Scugog, Lake Simcoe and Georgian Bay of Lake Huron. The region is the most densely populated and industrialized in Canada. Based on the 2021 census, with a population of 7,759,635 people in its core and 9,765,188 in its greater area, the Golden Horseshoe accounts for over 20 percent of the population of Canada and more than 54 percent of Ontario's population. The population of the greater area is estimated to have exceeded 11,000,000 people in 2024. The Golden Horseshoe is part of the Quebec City–Windsor Corridor, itself part of the Great Lakes megalopolis.

The core of the Golden Horseshoe starts from Niagara Falls at the eastern end of the Niagara Peninsula bordering the United States via New York and extends west, wrapping around the western end of Lake Ontario at Hamilton and then turning northeast to Toronto (on the northwestern shore of Lake Ontario), before finally terminating at Clarington in Durham Region. The term Greater Golden Horseshoe is used to describe a broader region that stretches inland from the core to the area of the Trent–Severn Waterway, such as Peterborough, in the northeast, to Barrie and Lake Simcoe in the north, and to the Grand River area, which includes cities such as Brantford and Guelph, to the west. The extended region's area covers approximately 33,500 km (13,000 sq mi), out of this, 7,300 km (2,800 sq mi) or approximately 22 percent of the area is covered by the environmentally protected Greenbelt. The Greater Golden Horseshoe forms the neck of the Ontario Peninsula.

The Welland Canal is a ship canal in Ontario, Canada, and part of the St. Lawrence Seaway and Great Lakes Waterway. The canal traverses the Niagara Peninsula between Port Weller on Lake Ontario and Port Colborne on Lake Erie, and was built because the Niagara River—the only natural waterway connecting the lakes—was unnavigable due to Niagara Falls. The Welland Canal enables ships to ascend and descend the Niagara Escarpment, and has followed four different routes since it opened.

The Welland Canal passes about 3,000 ships which transport about 40 million tonnes (88 billion pounds) of cargo a year. It was a major factor in the growth of the city of Toronto, Ontario. The original canal and its successors allowed goods from Great Lakes ports such as Cleveland, Detroit, Milwaukee, and Chicago, as well as other heavily industrialized areas of the United States and Ontario, to be shipped to the Port of Montreal or to Quebec City, where they were usually reloaded onto ocean-going vessels for international shipping.

The Niagara Frontier refers to the stretch of land in the United States that is south of Lake Ontario and north of Lake Erie, and extends westward to Cleveland, Ohio. The term dates to the War of 1812, when the northern border was in contention between the United States and British forces in Canada. It refers only to the land east of the Niagara River and north of Lake Erie within the United States. The western side of the Niagara River, on the Canada/Ontario side, is the Niagara Peninsula; it is considered part of the Golden Horseshoe.

The Niagara Frontier is part of the region known as Western New York State. The Niagara Frontier also forms the eastern part of the Great Lakes North Coast. Its southeastern boundary forms what is known as ski country, as it includes the northernmost area of the Appalachian Mountain foothills.

The Raid on Port Dover was an episode during the War of 1812. American troops crossed Lake Erie to capture or destroy stocks of grain and destroy mills at Port Dover in Upper Canada, which were used to provide flour for British troops stationed on the Niagara Peninsula. At the instigation of Lieutenant Colonel John B. Campbell and without sanction from his superiors or the government of the United States, the Americans also destroyed private houses and other property, prompting British commanders to demand reprisals in other theatres of the war. To some degree, the burning of Washington by the British later in the year was influenced by the American actions at Port Dover.

Niagara-on-the-Lake is a town in Ontario, Canada. It is located on the Niagara Peninsula at the point where the Niagara River meets Lake Ontario, across the river from New York, United States. Niagara-on-the-Lake is in the Niagara Region of Ontario and is the only town in Canada that has a lord mayor. It had a population of 19,088 as of the 2021 Canadian census.

Niagara-on-the-Lake is important in the history of Canada: it served as the first capital of the province of Upper Canada, the predecessor of Ontario. It was called Newark from 1792 to 1797. During the War of 1812, the town, the two former villages of St. David's and Queenston, and Fort George were the sites of numerous battles following the American invasion of Upper Canada, and the town was razed. Niagara-on-the-Lake is home to the oldest Catholic church, the second-oldest Anglican church in Ontario, and the oldest surviving golf course in North America.