Q. Which nation has the longest land border in the world? Answer:
China
Notes: China has the longest land border in the world. Its land border measures 22,147 kilometres. It borders more number of nations than any other country except Russia. China shares its land border with 14 nations such as Vietnam, Laos, Myanmar, India, Nepal, Afghanistan, Pakistan, Tajikistan, Kyrgyzstan, Kazakhstan, Russia, Mongolia and North Korea.