London is a city in Southwestern Ontario, Canada, situated along the Quebec City–Windsor Corridor. The city has a population of 366,151 according to the 2011 Canadian census. London is the seat of Middlesex County, at the forks of the non-navigable Thames River, approximately halfway between Toronto, Ontario and Detroit, Michigan. The City of London is a separated municipality, politically separate from Middlesex County, though it remains the official county seat.

London was first settled by Europeans between 1801 and 1804 by Peter Hagerman and became a village in 1826. Since then, London has grown into the largest Southwestern Ontario municipality, annexing many of the smaller communities that surrounded it. The city has developed a strong focus towards education, health care, tourism, and manufacturing.

London is home to Fanshawe College and the University of Western Ontario, which contributes to the city's reputation as an international centre of higher education, scientific research and cultural activity. The city hosts a number of musical and artistic exhibits. London's festivals contribute to its tourism industry, but its economic activity is centred on education, medical research, insurance, and information technology. London's university and hospitals are among its top ten employers. London lies at the junction of Highway 401 and 402, connecting it to Toronto, Detroit, and Sarnia. It also has an international airport, train and bus station.

London ⁱ/ˈlʌndən/ is the capital city of England and the United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its founding by the Romans, who named it Londinium. London's ancient core, the City of London, largely retains its square-mile mediaeval boundaries. Since at least the 19th century, the name London has also referred to the metropolis developed around this core. The bulk of this conurbation forms the London region and the Greater London administrative area, governed by the elected Mayor of London and the London Assembly.

London is a leading global city, with strengths in the arts, commerce, education, entertainment, fashion, finance, healthcare, media, professional services, research and development, tourism and transport all contributing to its prominence. It is the world's leading financial centre alongside New York City and has the fifth-largest city GDP in the world (and the largest in Europe). London has been described as a world cultural capital. It was the world's most visited city during 2011 and London Heathrow is the world's busiest airport by number of international passengers. London's 43 universities form the largest concentration of higher education in Europe. In 2012 London will become the first city to host the modern Summer Olympic Games three times.

Ontario /ɒnˈtɛərioʊ/ is one of the provinces of Canada, located in east-central Canada. It is Canada's most populous province or territory and fourth largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa.

Ontario is bordered by the province of Manitoba to the west, Hudson Bay to the north, Quebec to the east, and to the south by the U.S. states of Minnesota, Michigan (portions to the west), New York (portions to the east), Ohio and Pennsylvania. All but a small part of Ontario's 2,700 km (1,677 mi) border with the United States follow inland waterways: from the west at Lake of the Woods, eastward along the major rivers and lakes of the Great Lakes/St. Lawrence River drainage system. These are the Rainy River, the Pigeon River, Lake Superior, the St. Mary's River, Lake Huron, the St. Clair River, Lake St. Clair, the Detroit River, Lake Erie, the Niagara River, Lake Ontario, and along the St. Lawrence River from Kingston, Ontario to the Quebec boundary just east of Cornwall, Ontario.