Alaska and Hawaii
Alaska and Hawaii do not border any other state.
Hawaii
Maine.
Many people think the answer to this question is Tasmania, but this is incorrect. All of Australia's states share a border with another state. What most people do not know is that even Tasmania, the island state, shares a land border with Victoria. The border is nothing more than a 0.085 km long rocky outcrop at latitude 39° 12' S known as Boundary Islet.
South Australia borders the most states and territories in Australia. South Australia shares borders with Western Australia, the Northern Territory, Queensland, New South Wales and Victoria.
Alaska and Hawaii are the only two states that do not share a border with another state.
Tasmania has no border with South Australia.
Morris, Somerset
The only state to share a border with all other mainland states in Australia is South Australia. It touches Western Australia on the west, the Northern Territory and part of Queensland on the north, and Queensland, New South Wales, and Victoria on the east.
Hawaii is the only state out of the 50 US states that does not share a border with any other state.
the state that shares a border with Russia