Transport & space · c. 1275

Portolan chart

Compass-bearing sea charts map coasts accurately enough to plot a voyage.

Portolan charts, crisscrossed with compass rhumb lines, appear in the Mediterranean in the late 13th century; the Carta Pisana of about 1275 is the oldest surviving. They showed coastlines with striking accuracy. Charts plus compass turned navigation into a repeatable craft.

See it in the living tree Wikipedia

Arcs above join it to what it stood on, arcs below to what it led to. The bar places this stretch on the tree's whole timeline.

What it built on 1

Magnetic compass 1040

What it led to 1

First circumnavigation 1522

Related measurements

The dashed line marks when it first worked.

World trade as a share of GDP since 1500 Latest: 1950-now (PWT): 57.8 % of GDP (2023) Source: Our World in Data

Transatlantic crossing time Latest: 3.5 hours (1976) Source: Wikipedia: Transatlantic crossing, duration list; Geography of Transport Systems: liner transatlantic crossing times