The Signal Flags Museum
How humans sent messages across distance without wires — from beacon fires and Chappe's optical telegraph to the International Code of Signals still hoisted on every ship at sea. Spell phrases as code flags, learn the semaphore alphabet, and trace 4,000 years of visual communication.
International Code of Signals
Type a message; each letter becomes its ICS flag, stacked top-to-bottom on a virtual halyard. Single flags also have stand-alone meanings — most reserve themselves for the most urgent or common situations, chosen so even a wrong hoist in the wrong context stays unambiguous.
Hover or tap any flag to see what it says on its own — "Bravo" alone means "I am taking on dangerous cargo"; "Quebec" alone means "my vessel is healthy, please grant pratique."
The Collection
38 artifacts across maritime hoists, optical telegraphy, semaphore systems, phonetic alphabets, and military and modern signaling. Click any card to copy its description.
No artifacts in this category.
From Beacon Fires to NATO Phonetic
From 1184 BC to 1999 — almost three thousand years of getting words from one hill, ship, or fortress to another.
Hands-on Instruments
A semaphore figure that poses the alphabet, a clickable library of every ICS flag, and a quick-reference for the international distress signals you hope you never need.
The semaphore alphabet uses two flags held in seven possible positions per arm. Type a word and watch the figure spell it out — one letter per second. The letter J is signalled by the "alphabet" indicator first, since J was added to most European alphabets after the system was designed.
Click any flag to see what a single hoist of that flag means at sea. The single-letter meanings are reserved for the most urgent or common situations — they're chosen so even the wrong flag in the wrong context stays unambiguous.
A quick reference of the visual and audible distress calls every signal-flag exam still asks about. Most are now layered on top of GMDSS satellite distress, not replaced by it — when the radios are down, the flags still work.