Read the surviving log
Every case starts with a captain's log: courses, weather and sightings. Some pages are missing, and that is the point.
Historical navigation mysteryVoyage Trace
Rebuild the routes of lost sailing ships from what survived: a water-stained captain's log, the wind, the current and the Sun. One small step at a time, until the route returns to the chart.
How it works
From a torn log to a route on the chart
Every case is a lost voyage with a broken record. You work it the way a navigator would, one small task per screen.
Analyze the evidence
Wind, current, speed, time and the Sun are laid out as cards. Each is marked ✓ Confirmed, ~ Estimated or ? Unknown.
Rebuild one point at a time
One small task per screen: set a direction, place a point, account for the current, match an observation.
Watch the route return
The route grows on the chart as you work. Every result is an estimate with an honest confidence level.
Why you'll keep tracing
Real navigation. Honest answers.
No GPS, no shortcuts: just the methods sailors trusted for centuries, and a record full of gaps.
Six lost voyages
From a supply brig bound for Iceland in 1786 to a whaler pushing toward Spitsbergen and a barque among Labrador icebergs. Each one is a case to crack.
The methods sailors trusted
Dead reckoning, noon sights, chronometer longitude and bearings on a headland: work the route with the real tools of historical navigation.
Evidence you can weigh
Every clue says how far you can trust it, so a decision is never a blind guess.
✓ Confirmed~ Estimated? Unknown
An honest confidence level
Historical routes can never be perfectly certain. Every reconstruction shows how likely it is, with dashed lines where the record is missing.
An archive and a guide
18 illustrated articles on ships, charts and instruments, plus 8 guide topics with small diagrams to try, from bearings to the noon Sun.
Offline and private
No accounts, no ads, no analytics. Everything is built into the app, works without a connection and stays on your iPhone.
The casebook
Six voyages. Six silences in the record.
Fictional, historically inspired expeditions across the northern waters, built on real navigation methods and real coastlines.
The Northern Passage
5 daysRecommended level: EASY
Brig Calliope
The Missing Meridian
2 daysRecommended level: EASY
Cutter Linnet
White Horizon
4 daysRecommended level: STANDARD
Barque Hesper
The Pale Crossing
4 daysRecommended level: STANDARD
Barque Selkirk
The Silent Strait
3 daysRecommended level: MYSTERY
Sloop Solveig
The Frozen Gate
4 daysRecommended level: MYSTERY
Brig Kestrel
EASY
Most positions and readings survived. A gentle first case.
STANDARD
Some courses and currents are missing. Read the clues.
MYSTERY
Most of the route must be worked out from scattered notes.
The archive & the guide
Learn the sea as you go
Short, visual articles and plain-word answers, always one tap away from the case you're working.
Contact
Message in a bottle
A question, an idea for a new voyage, or a mistake you spotted in a log? We read every message.
hsgjds525@gmail.com
Every route leaves a trace.
Open the first case tonight. The log is waiting, and so is the sea.
Calm, clever & quietly addictive