What is Globe Weaver — Travel Planning Puzzle
Globe Weaver drops you onto a map of twenty-three countries with a destination, a few required stops and a small wallet of tickets. Every hop has its transport chosen by the map, not by you: a car for a short land hop, a train for a long one on the same continent, a boat to an island within 4,500 km, and a plane for everything else. Each hop spends one ticket of that kind and a slice of a travel budget. The destination stays behind a padlock until every stop is ticked off, so the question is never where to go, only in which order.
The distances are real. Each country sits at its approximate geographic centre and the game measures great-circle distance with the haversine formula, so Portugal to Spain is 400 km and Spain to New Zealand is 19,885 km. What makes a puzzle of those numbers is that the price in seconds is not proportional to them. A plane crosses almost any gap for nine to thirty seconds, while the longest train, Morocco to South Africa, costs forty-four, and the longest sea crossing, Thailand to Japan, thirty-seven. Read the seconds, not the kilometres. Between nine and fourteen countries share the map at any one time, and most of them are decoys with no part in the route at all.
How to play
- Press Start puzzle. A pin marks where you are, parcels mark the stops you must visit, and a padlock marks the destination you cannot enter yet.
- Tap any country to plan a hop. The panel names the transport, the distance, the cost in seconds and whether your tickets and budget cover it.
- Press Travel to commit, or tap the same country again. Undo returns the ticket and the seconds, so trying an order out and taking it back costs nothing.
- Clear every parcel to unlock the destination, then travel there. Your score is the budget and the tickets left over, minus eight points for each hop.
Strategies that work
- Only twelve of the 253 country pairs are sea crossings, and every one touches the United Kingdom, Japan, Australia or New Zealand. One boat ticket therefore names one specific hop in your route. Work out which hop that has to be first, and the rest of the order usually settles itself.
- Never judge a hop by its distance. The plane does 900 km/h against the boat's 130, so Turkey to Brazil, 10,750 km, costs twenty seconds while the United Kingdom to Turkey, a third as far, costs twenty-nine by sea. The seconds in the panel are the real price.
- The destination is always the country farthest from your start, so you can name it before looking at the stops: from anywhere in Europe it is New Zealand, from China it is Argentina. Plan backwards from that last hop, because its ticket is the one not to spend early.
- From level six the tickets are exactly what one good route needs, with nothing spare. Read the ticket row as a bill of materials and count the hops of each kind your intended order would need. If the counts disagree, the order is wrong, never the board.
- Hovering and tapping cost nothing; only Travel spends anything, so check every candidate first. The tooltip gives the transport, the kilometres, the seconds and the exact reason a hop is refused. All seven car hops sit inside Europe, so elsewhere your cheapest move is usually a short flight.
A little history
Globe Weaver is an original puzzle written for puzzle-me.com. It belongs to the family of constrained routing problems: the travelling salesman problem asks for the cheapest tour through a set of points, and this game keeps that skeleton while imposing the transport of each leg by geography and counting out the tickets in advance. The board is not invented. The twenty-three countries sit at their approximate geographic centres, and every distance is a great-circle distance computed with the haversine formula on a sphere of radius 6,371 km, the standard mean radius of the Earth.
Frequently asked questions
Do I need to install anything or make an account?
No. Globe Weaver runs in the browser on a computer and on a telephone, where the map shrinks and the country markers grow so they stay easy to tap. Your level, best score and trip count live in the browser's local storage.
Is the Daily Challenge the same puzzle for everybody?
Yes. The seed comes from the date in UTC and the difficulty is pinned to level six — three stops, exact tickets, the tightest budget — whatever level you have reached in free play. It also leaves your own progression untouched.
How is the score worked out?
Each second of budget left is worth twenty-five points, each unspent ticket eighty and the level number a hundred; every hop costs eight. A tight, cheap order therefore scores far above a merely legal one, and giving up at a dead end still records a small score.
