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Longest international border -

The border between the United States and Canada is the longest international border in the world. The terrestrial boundary (including boundaries in the Great Lakes, Atlantic, and Pacific coasts) is 5,525 mi (8,891 km) long.

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Creation of the border -

The Treaty of Paris of 1783 ended the American Revolutionary War between Great Britain and the United States. In the second article of the Treaty, the parties agreed on all boundaries of the United States.

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The border is established -

Included in the Treaty was the boundary to the north along then-British North America.

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Two sections -

The land border has two sections: Canada's border with the contiguous United States to its south, and with the US state of Alaska to its west.

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States and provinces -

Eight out of 13 provinces and territories of Canada and 13 out of 50 US states are located along this international boundary.

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Longest border against Canada -

Of these, Alaska is the US state that has the longest border against Canada, at 1,538 mi (2,475 km).

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Longest border against the USA -

Ontario, meanwhile, is the Canadian province that has the longest border against the United States, at 1,682 mi (2,727 km).

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Shortest border against Canada -

Pennsylvania is the US state that shares the smallest length of the border with Canada, at 42 mi (68 km).

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Shortest border against the USA -

Alberta's border with the US is 185 mi (298 km), making this the smallest boundary length with the United States.

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Northwest Angle of Minnesota -

The quirkiest section of the border is the oddly-shaped Northwest Angle of Minnesota (top of photograph). It covers an area of 596 sq mi (1,543 sq km), 473 sq m (1,225 sq km) of which are water. This area is the northernmost point in the contiguous United States.

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A geographic oddity -

The Northwest Angle sticks up like a chimney on the roof of Minnesota, reaching into Ontario and Manitoba. This geographic oddity is actually a result of bad mapping. In the 19th century, existing surveys of the area were at best rudimentary. The British tried to negotiate bringing the Angle back into Canada, but for historical reasons and pride, the United States never wanted to change anything that had been negotiated in the Treaty of Paris.

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Border crossings -

There are currently 119 legal land border crossings between the United States and Canada, 26 of which take place at a bridge or tunnel. The busiest of these in terms of trade volume is the Ambassador Bridge, which links Detroit, Michigan, with Windsor, Ontario.

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Trail crossings -

You can hike freely and legally into Canada from the United States by following the Pacific Crest Trail into E. C. Manning Provincial Park in British Columbia. From Canada, however, hikers require an advance permit to enter US territory. Elsewhere, the Fourth Connecticut Lake Trail (New Hampshire/Quebec) crosses several times while following the border vista before heading back to the United States.

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Railroad crossings -

There are currently 31 rail points of entry that connect the US with Canada, and four of these rail border crossings include passenger routes. Pictured is Vancouver's Pacific Central Station, which connects rail passengers with Seattle.

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Cross-border airports -

Curiously, there are six airports that have a portion of their facilities in both Canada and the United States. For example, Piney Pinecreek Border Airport (pictured) is located in Piney, Manitoba, and Pinecreek, Minnesota.

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Cross-border ferry crossings -

Although most people travel between Canada and the United States by vehicle or airplane, there are a number of ferry crossings between the countries. For instance, the CAT high speed car ferry (pictured), connects Portland, Maine, with Yarmouth, Nova Scotia.

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Peace Arch Border Crossing -

The Peace Arch Border Crossing, a major border crossing between Interstate 5 and British Columbia Highway 99, is set within Peace Arch Park, so named for the monument built on the exact US–Canada boundary.

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Borderline communities -

Most Canadians live relatively near the US border. In fact, 90% of the country's population live within 100 mi (160 km) of the boundary. Toronto, for example, is only 15 mi (25 km) away from the nearest border crossing.

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No-Touch Zone -

A 20-foot (six-meter) strip is set around the Canada-United States border. This clearcut feature is the work of the International Boundary Commission, which calls it a "visible line between friendly neighbors." Others have described it as the "no-touch zone." This giant vacant space runs most of the length of the border that passes between forested areas.

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Cross-border buildings -

A number of buildings straddle the Canada-United States border. These so-called line houses sit directly on the international boundary, examples of which include the Haskell Free Library and Opera House, half of which lies in Derby Line, Vermont, and the other in Stanstead, Quebec. The boundary is marked by a black line on the floor of its reading room.

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Province Island, Quebec -

Between Quebec and Vermont is Province Island. This slither of land lies primarily in Canada, though a small portion of the island is actually situated in the US state, lying south of the 45th parallel.

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Split personality -

The aptly named Canusa Street in Beebe Plain, Vermont, is the only portion of the Canada–United States border split down the middle of a street. Pictured is the U.S. Customs and Border Protection crossing.

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Natural wonder -

Arguably the most spectacular portion of the Canada-US border is Horseshoe Falls and the Niagara River, which mark the Ontario-New York boundary. Lakes and waterways make up most of Ontario's borders with the United States.

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Walking over Niagara Gorge -

French acrobat Charles Blondin (1824–1897) owed his celebrity and fortune to a daring feat in 1859 when he crossed the Niagara Gorge on the Canada–US border on a tightrope. The bridge in the background is the Niagara Falls Suspension Bridge.

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Mohawk Nation at Akwesasne -

The boundary runs through the middle of the Mohawk Nation at Akwesasne. The territory straddles the international border and the provincial borders of Ontario and Quebec. Despite this, the residents consider themselves to be one community.

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Cross-border drug smuggling tunnel -

In 2005, US and Canadian law enforcement officers (pictured) arrested three men after the discovery of a drug smuggling tunnel leading from a house in Aldergrove, British Columbia, under the border to a house in Lynden, Washington.

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Rum-running the border -

The arrests reminded authorities of the Prohibition era of the 1920s. While it was illegal to produce and imbibe moonshine within the borders of the United States, that wasn't the case in neighboring Canada and Mexico. Breweries and distilleries flourished in these countries, and smuggling and rum-running was rife.

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Say cheese! -

According to research undertaken at Douglas College in British Columbia, cheese is one of the most smuggled items that travelers try to bring into Canada. This is due to the Canadian government's protection of dairy farmers, and the high prices cheese commands in the country. Those caught in the attempt risk paying a hefty fine.

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Foreign bodies -

Bizarrely, coffins are exempt from the harmonized sales tax and other duties, under what is known as the Coffin or Casket Remission Order.

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A safe haven -

As many as 40,000 young Americans crossed the border into Canada to avoid being drafted into the Vietnam War. Many US citizens who took refuge north of the border assimilated in the country and continued to reside there decades after the war's end in 1975.

Sources: (International Boundary Commission) (Federal Railroad Administration) (NPR) (NBC News) (Douglas College)

See also: The longest and shortest wars in history

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