Question: What des the Boston-Washington corridor have in common with the Quebec City–Windsor Corridor?
Context: ViaFast (corporately styled VIAFast) was an abandoned passenger rail plan that would have cut Via Rail's trip times throughout the Quebec City – Windsor Corridor.  ViaFast did not propose true high-speed service throughout the service area, but a series of smaller upgrades to avoid known bottlenecks and provide improved performance at a fraction of the price of entirely new lines.  It aimed to reduce the Toronto-Montreal time by about one hour to 3.5 hours, halving the Montreal-Quebec City time to 2 hours, and reducing Toronto-Windsor time by an hour to 3.5 hours. The Quebec City–Windsor Corridor is the most densely populated and heavily industrialized region of Canada.  As its name suggests, the region extends between Quebec City in the northeast and Windsor, Ontario in the southwest, spanning 1150 km .  With more than 18 million people, it contains over half of the country's population and three of Canada's five largest metropolitan areas according to the 2016 Census.  In its relative importance to Canada's economic and political infrastructure, it has many similarities to the Northeast megalopolis in the United States.  The name was first popularized by Via Rail, which runs frequent passenger rail service in the Quebec City–Windsor Corridor in its service area known as "The Corridor". The Golden Horseshoe 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 Georgian Bay.  Most of it includes the Greater Toronto and Hamilton Area, while the region is a significant part of the Quebec City–Windsor Corridor and the Great Lakes Megalopolis. Rapido was the brand name for the Canadian National Railway's (CN) express passenger train service in the Quebec City–Windsor Corridor.  "Rapido" service was introduced on October 31, 1965 and lasted until the end of CN passenger train service with its transfer to VIA on October 29, 1978. Trois-Rivières (] , ) is a city in the Mauricie administrative region of Quebec, Canada, located at the confluence of the Saint-Maurice and Saint Lawrence Rivers, on the north shore of the Saint Lawrence River across from the city of Bécancour.  It is part of the densely populated Quebec City–Windsor Corridor and is approximately halfway between Montreal and Quebec City.  Trois-Rivières is the economic and cultural hub of the Mauricie region.  The settlement was founded on July 4, 1634, the second permanent settlement in New France, after Quebec City in 1608. London is a city in Southwestern Ontario, Canada along the Quebec City–Windsor Corridor.  The city has a population of 383,822 according to the 2016 Canadian census.  London is at the confluence of the Thames River, approximately 200 kilometers from both Toronto, Ontario and Detroit, Michigan; and about 230 kilometers from Buffalo, New York.  The City of London is a separated municipality, politically separate from Middlesex County, though it remains the county seat. Windsor railway station is the western terminus of Via Rail's Quebec City–Windsor Corridor and literally at the end of the line it buffers onto the Detroit River.  Located in the Walkerville area of the city of Windsor adjacent to the Hiram Walker Distillery, the station is served by eight Via Rail trains daily which originate in Toronto. Cornwall is a city in Eastern Ontario, Canada, and the seat of the United Counties of Stormont, Dundas and Glengarry.  Cornwall is Ontario's easternmost city, located on the Saint Lawrence River in the Quebec City–Windsor Corridor along Ontario Highway 401, and is the urban centre for surrounding communities, including Long Sault and Ingleside to the west, Mohawk Territory of Akwesasne to the south, St. Andrew's and Avonmore to the north, and Glen Walter, Martintown, Apple Hill, Williamstown, and Lancaster to the east. London, a Canadian city located in Southwestern Ontario along the Quebec City–Windsor Corridor, has received numerous royal visits since 1939.  The United Kingdom's current monarch, Queen Elizabeth II, first visited in 1973, and subsequent visits have been made by other members of the British Royal Family since then. The Northeast megalopolis (also Boston–Washington Corridor or Bos-Wash Corridor) is the most heavily urbanized region of the United States, running primarily northeast to southwest from the northern suburbs of Boston, Massachusetts, to the southern suburbs of Washington, D.C., in Northern Virginia.  It includes the major cities of Boston, Providence, Hartford, New York City, Philadelphia, Wilmington, Baltimore, and Washington, D.C., along with their metropolitan areas and suburbs as well as many smaller urban centers.
Answer: economic and political infrastructure