Quebec and New brunswick
Asia
Pennsylvania borders Maryland to the south.
Quebec and New Brunswick ==================== The Chignecto Isthmus, which connects New Brunswick and Nova Scotia, is only 24 miles across.
The Great Lakes border the U.S. states of Minnesota, Wisconsin, Illinois, Indiana, Michigan, Ohio, Pennsylvania, and New York.
When countries share a border it is referred to as a "common or shared" border.
Quebec and New Brunswick ==================== The Chignecto Isthmus, which connects New Brunswick and Nova Scotia, is only 24 miles across.
The two provinces in Canada with the shortest border are Prince Edward Island and Nova Scotia. The border between them is primarily defined by the Northumberland Strait, which separates the two regions. The distance across the strait is minimal, making it the shortest border between Canadian provinces.
No provinces share the northern border. Alberta Saskatchewan and part of B.C share the southern border though.
Asia
British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, and Quebec are the Canadian Provinces that shares their southern border with USA.
Two provinces in Canada share a southern border with the United States: British Columbia and Alberta. British Columbia borders the U.S. states of Alaska and Washington, while Alberta shares its border with Montana. Additionally, there are other provinces that share the border with the U.S. through various territories, but only British Columbia and Alberta have the southern border directly.
The province of British Columbia shares a border with only one other province - Alberta. The Province of Newfoundland and Labrador shares a border with only one other province - Québec. All the other provinces share a border with at least two other provinces.
British Columbia and Yukon Territiry
British Columbia, Alberta and Saskatchewan
No US States, however two Canadian Provinces share border and there is a maritime border with Russia.
Pennsylvania borders Maryland to the south.
No US State has a border with Alaska but two Canadian Provinces, British Columbia and the Yukon Territory share a common border with the State.