You can go all the way from the UK to Australia or New Zealand by sea, either a leisurely direct voyage by infrequent round-the-world cruise, or by one of the few remaining passenger-carrying freighters, sometimes with the need to switch ships in either the USA or SE Asia.

While it might seem physically impossible on a flat map due to the massive landmasses of Africa or South America, you can indeed sail from the UK to New Zealand in a "straight line" when accounting for the Earth's curvature. This route involves following a Great Circle path that heads south-southwest from the British Isles, passing through the Atlantic Ocean and just clipping the edge of the formidable Drake Passage between South America and Antarctica. The journey covers approximately 12,000 nautical miles (over 20,000 km) and takes you through some of the most treacherous waters on the planet. Historically, this wasn't the standard route; sailors preferred the "Clipper Route" via South Africa and Australia to catch the prevailing winds. While modern GPS makes plotting this direct line possible, the extreme conditions near Cape Horn mean most commercial and leisure vessels still prefer the safer, more traditional passages through the Suez or Panama Canals.