Which country has the southernmost national capital city?

Wellington, New Zealand, is the southernmost national capital city in the world.

The capital lies at about 41°17′ south on the southwestern tip of New Zealand’s North Island, between Cook Strait and the Remutaka Range. Its latitude places it farther south than Canberra, Santiago, Buenos Aires, and every other capital of a sovereign state.

Wellington became New Zealand’s capital in 1865, replacing Auckland. Its central position helped resolve political and administrative concerns about governing both the North and South Islands. The city’s harbour and narrow strips of buildable land have shaped its dense urban form and transport links.

The capital’s location also explains two famous characteristics. Wellington is exposed to the strong westerly winds of the Roaring Forties and is widely described as the world’s windiest city by average wind speed. It is also a major gateway to New Zealand’s South Island via Cook Strait ferries. “Southernmost capital” refers to national capitals of sovereign states, not every administrative capital or Antarctic research settlement.