Which sea lies between Australia and New Zealand?

The Tasman Sea, about 2,000 kilometres across - which is why the two countries call each other neighbours and are further apart than London is from Moscow. Crossing it is the ditch in Australian and New Zealand slang, and doing it alone by rowing boat or kayak is a recognised feat that several people have died attempting.

It is one of the roughest stretches of water regularly crossed by aircraft and ships, sitting in the band of westerlies that circle the Southern Ocean unobstructed by land - the roaring forties. There is no continent between here and South America to slow the wind down, so the swell builds over thousands of kilometres.

Underneath it is a continent. Zealandia is a mass of continental crust about five million square kilometres in extent, 94 per cent submerged, of which New Zealand and New Caledonia are the parts still above water. It was recognised in a 2017 paper as meeting every criterion for a continent except being dry, and it was fully mapped only in 2023 - a landmass the size of India that nobody had drawn.