How to play
One hex on this chart is a lie.
A cartographer drew it, and hid one false entry in it — a single hex drawn as something it is not. Every survey note you are given is true. Only one hex can satisfy all of them at once. Find it and file your correction. You get three.
Find the lie
Every note the cartographer leaves you is TRUE, and only one hex on the chart can satisfy all of them at once — that hex is the lie. Here there is one note. Tap the hex it points to.
- The lie lies north-east of every shoal.
Ground
- He · heath
- Sc · scree
- Sh · shoal
Click the hex the notes point to.
Reading the chart
Every ground is engraved linework on tinted paper, the way a printed hydrographic chart draws shallows, rubble and marsh — never a flat colour block. Each hex also carries its two-letter code. The chart key under the board names every symbol on today’s island, and a note names its landmark exactly, so the key is worth opening before you start.
Dashed lines are district boundaries — the sheets a note means when it says Sheet II. The solid outer edge is coastline.
Filing a correction
Select a hex and file. You get three corrections. A refused correction is stamped on the chart with an X in the cartographer’s ink — distinct from your own single strike, so you can never mistake the chart’s verdict for your own reasoning. Spend all three and the lie is revealed.
The chart here, and the chart in the app
A new chart is drawn daily at 5am New York time, and it is the same island in the browser and on iPhone — the two run the identical engine. The web serves the Casual and Standard tiers. Hard, streaks, ratings, the career ladder and daily duels live in the app, and the Fiendish chart is part of the Cartographer’s Guild membership.
Sign in and a chart you finish here counts: it adds to your solve total and keeps your streak alive, and both are the same numbers the app reads — finish the same chart on both and it counts once. Ratings, career points and duels stay in the app. Signed out, nothing is recorded at all.
Frequently asked questions
What is The Cartographer’s Lie?
A daily deduction puzzle on a hand-drawn nautical chart. One hex of the map has been drawn as something it is not — the lie. Every survey note you are given is true, and only one hex can satisfy all of them at once. You find that hex and file a correction.
How do I play?
Read the survey notes and eliminate hexes. Each note — a compass bearing, a count of neighbours, a sheet location, a ground type — is true of the lie, so together they narrow the island to a single hex. Select that hex and file your correction. You get three corrections before the lie is revealed.
What does a compass bearing note mean exactly?
Bearings are strict. “The lie lies north-east of every beacon” means the hex is north of every beacon AND east of every beacon, both at once — not roughly in that direction. Two bearings that sound contradictory corner the lie between them.
What does a “Not so:” note mean?
On Hard charts, a note beginning “Not so:” is false of the lie. Read the sentence without the “Not so”, find every hex it would be true of, and rule them all out — the lie is elsewhere.
What are soundings on a Fiendish chart?
Every hex prints a depth in fathoms. Exactly one printed number is a misprint, and that hex is the lie. The notes describe its true depth — what the sea actually measures — which is never the printed number. You name both the hex and its true depth.
Is it free, and when does a new puzzle appear?
It is free to play in the browser. A new chart is drawn every day at 5am New York time, the same chart for every player. The Casual and Standard tiers are on the web; Hard, streaks, ratings and duels are in the free iPhone app, and the Fiendish chart is part of the Cartographer’s Guild membership.