Know your Nautical Terminology
We continue our new series of items highlighting with humanity's early exploration of Earth's oceans, lakes, and rivers and leading to the use of watercraft for transportation and commerce.
Last month I covered the introduction of sails. It does little to be able to move faster with sails if you don't know how to get to your destination.
Portolan charts (late 13th century, especially the Carta Pisane around 1275–1290) are the earliest known surviving maps specifically designed and used for practical water/sea navigation. These medieval European nautical charts, primarily from the Mediterranean region (Italy, Catalonia, etc.), marked a shift from earlier schematic or cosmological world maps to functional tools for mariners. They featured accurate coastlines, ports, harbors, and networks of rhumb lines (straight lines radiating from compass roses) that helped pilots plot courses using compass directions and wind information. They were typically drawn on vellum/parchment and used by merchants and sailors for coastal and somewhat open-sea travel in the Mediterranean and nearby waters.
Ancient textual sailing directions, Rutters, ("periploi" in Greek or pilot books) existed much earlier, from at least the 6th century BC, describing routes, landmarks, winds, and hazards along coasts (e.g., for Greek, Phoenician, or Roman sailors). These were not graphical maps but written guides, sometimes paired with rudimentary sketches.
A rutter (also spelled "routier" in French or "roteiro" in Portuguese) is a mariner's handbook consisting of written (textual) sailing directions. It served as a practical guide for navigators, detailing routes, courses, distances, landmarks, hazards, tides, depths, harbors, and other essential information needed to sail safely from one place to another.
Many historians believe the detailed written information in rutters/portolani provided the empirical data from which the first portolan charts were compiled in the late 13th century. The widespread use of the magnetic compass in European navigation from the 13th century onward allowed rutters to specify precise compass courses, distinguishing them from purely landmark- or star-based ancient guides.
The Carta Pisane 
SpyNavy
Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)
