Santa realises he can save time by only visiting the “What Three Words” squares on land (bad luck, seamen!). Make the same assumptions as in challenge 3, with the additional constraints:
1) Exactly two thirds of the world is covered with water, and doesn’t need visiting
2) Antarctica is a circle of radius 2000 km, and doesn’t need visiting
3) Squares on Europe, Asia, Oceania (OK, I know that’s a bit of a stretch), and Africa can all be visited on a single route passing horizontally or vertically between adjacent squares, starting with his base in Northern Scandinavia and finishing in South Africa.
4) Squares on South America and North America can similarly be covered with a route starting at the Cape Horn and finishing in Newfoundland.
5) The transatlantic trip from the Cape of Good Hope to Cape Horn is exactly 6000 km, and the trip from Newfoundland, via Greenland and Iceland, back to his base is another 3900 km.
Now how long is his journey?