Great question and one that is often misunderstood.
Whilst most assume the closest country to Australia is New Zealand, this is actually incorrect.
The closest country to Australia is actually Papua New Guinea which is only 4km away from Australia.
The parts of Australia closest to Papua New Guinea are Boigu Island and Salibai Island in Northern Queensland – see the map below:
There are a number of neighbouring countries to Australia in the Asia and Pacific region. Generally, the neighbouring countries are under a 6 hour flight and can be reached fairly easily.
Which European Country is nearest to Australia?
The closest European country to Australia is Russia.
The part of Russia that is closest to Australia is the Khasansky District which neighbours China and North Korea.
Which Asian Country is nearest to Australia?
The closest Asian country to Australia is Papua New Guinea which is the closest country globally.
It’s important to remember that Australia is a huge country (nearly as big as the whole of Europe) and spans three different time zones so different parts of Australia are closer to certain countries.