Traditional maps show geography, but they do not show accessibility. An isochronic map colours the world by how long it takes to get there rather than how far away it lies. Sir Francis Galton drew the first in 1881, shading the globe in bands of equal travel time from London. Every place sharing a tint on this chart is reachable in the same span of hours, door to door — so the map measures the world in time, as the traveller truly meets it.
Every point on the chart is reckoned door to door: the journey to the aerodrome, two hours for check-in and security on international service (an hour and a half domestic), the scheduled flight, an hour or so to disembark and clear customs, and onward travel by road or rail at the prevailing speed of the country — swift upon the Shinkansen and the German autobahn, slow indeed across the Sahara, the Amazon and the Siberian taiga.
Where no nonstop service exists, the reckoning routes the traveller through the most favourable hub with a single connexion of 2¼ hours. Travel is presumed continuous, as Galton presumed it; no allowance is made for sleep, which the modern traveller forgoes at altitude regardless.
Flight times are typical scheduled outbound block times drawn from published schedules and tracking data: Qantas QF8 Dallas–Sydney averages 16 h 44 m and QF22 Dallas–Melbourne is scheduled at 17 h 35 m (Flightradar24; OAG); the Dallas/Fort Worth nonstop network — Doha, Dubai, Istanbul, Tokyo, Seoul, Hong Kong, Taipei, Shanghai, Brisbane, Auckland among it — follows current route listings (FlightConnections, 2026); Istanbul's network follows Turkish Airlines' published schedules — Istanbul–San Francisco at about 13½ h, Istanbul–Los Angeles near 14 h — with Sydney reckoned via connexion until the promised nonstop flies (Turkish Airlines; FlightConnections, 2026). Coastlines are Natural Earth 1:110m.
The tints are an honest abstraction, not a timetable: connexions assume the favourable case, overland speeds are regional averages, and the closure of Russian airspace to western carriers is respected in the routings. Times within a band should be trusted; minutes should not.