Cornwall.
Alaska and Hawaii are the only two states that do not share a border with another state.
no hawaii does not share a border with any other state in the united states
Hawaii is the only state out of the 50 US states that does not share a border with any other state.
Portugal is a European country that shares a border with only one other nation, Spain.
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.
All states but Alaska and Hawaii border at least one other state. Maine is the only state to border just one state.
The only countries in South America that share no border with Brazil are Ecuador and Chile.
Oman and Iran share only a sea border in the middle of the Gulf.
Africa
There are many island nations which share borders with each other. - The United Kingdom and the Republic of Ireland are both island nations and share a border with each other on the island of Ireland. - Haiti and the Dominican Republic are both island nations and share a border with each other on the island of Hispaniola. - Indonesia and Brunei are both island nations and share a border with Malaysia on the island of Borneo. Malaysia is not an island nation. - Indonesia and Timor Leste are both island nations and share a border with each other on the island of Timor. - Indonesia and Papua New Guinea are both island nations and share a border with each other on the island of New Guinea.
Only three countries share a border with Luxembourg. They are Belgium, France, and Germany.
Only 2, 3 if you count sea borders