Which is the largest sovereign country with no land borders?

Australia is the largest sovereign country with no land borders.

Australia covers about 7.69 million square kilometres and is surrounded by maritime boundaries rather than international land borders. Its nearest sovereign neighbours include Indonesia, Papua New Guinea, and Timor-Leste, but none shares a land boundary with Australia.

Australia is often called an island country, although it is also classified as a continent. Its absence of land borders distinguishes it from large continental states such as Russia, Canada, China, Brazil, and the United States. Other large island countries, including Indonesia and Madagascar, are substantially smaller.

Australia’s coastline faces the Indian and Pacific oceans and several associated seas. The country includes Tasmania and numerous smaller islands. Canberra is the national capital, and the population is concentrated mainly in coastal metropolitan areas rather than the arid interior.