Runway numbers aren't a sequence — they're the magnetic heading

The large white numbers on runway thresholds mark the magnetic heading rounded to the nearest ten degrees: runway 24 points to roughly 240 degrees, i.e. southwest — and the very same strip of concrete is called 06 when used from the opposite direction.

2026-08-30

A runway's number comes from the magnetic heading of its direction: the heading is divided by ten and rounded, so a heading of 237° gives runway 24. Since one strip is used in both directions, every runway has two numbers, differing by exactly 18 — that is, 180 degrees. In Prague, 06 and 24 share one strip of concrete, while 12 and 30 share the other. Where parallel runways with the same heading lie side by side, a letter tells them apart: L for left, C for centre, R for right. Where four or more parallel runways lie side by side, letters stop being enough — some runways then carry a number shifted by one, even though they point in the same direction.

Difference between both runway ends

18 (180°)

Parallel runways

suffix L / C / R

Runways in Prague (LKPR)

06/24 and 12/30

Highest number

36 (heading 360° — due north)

For the crew, the number is an instant check: once aligned with the runway axis, the compass must show roughly ten times the number painted in front of the window — if it doesn't, the aircraft is on the wrong runway. Which end is currently "in use" is decided by air traffic control mainly based on the wind: aircraft land and take off into the wind, so as the wind turns, the whole airport's traffic direction turns with it.

Flying into the wind matters because both takeoff and landing depend on speed relative to the air, not to the ground. A headwind does part of that work by itself: the aircraft lifts off and touches down at a lower speed relative to the runway, so it needs a shorter takeoff run and a shorter landing roll. A crosswind, on the other hand, makes landing harder — every aircraft type has its own limit, and once the wind exceeds it, traffic shifts to a runway that faces the wind better. That's another reason large airports have runways in two directions; in Prague, 06/24 and 12/30.

Which direction landings use in Prague

from our touchdown measurements, 10–29 Aug 2026

Shares are calculated from 4,436 landings for which our network measured the touchdown and assigned a runway. Landings against the prevailing southwesterly flow head precisely for runway 24.

Runway usage on the airport profile

Václav Havel Airport Prague

What else is painted on the runway

• Wide longitudinal stripes at the start mark the threshold — the point where an aircraft may first touch down. Arrows before them indicate a displaced threshold: that section can't be landed on, though taxiing on it is fine.
• A pair of stripes a bit past the threshold mark the touchdown zone — the target point where the aircraft should land, leaving enough runway left to brake to a stop.
• Solid yellow bars on taxiways before the runway entrance are holding points — you may not cross them without tower clearance.

The numbers aren't forever, though: the magnetic north pole slowly drifts, and magnetic headings shift along with it. Once the shift exceeds half of ten degrees, the airport renumbers the runway — repainting the thresholds and rewriting maps, navigation databases and the names of instrument approaches. A "new" runway in an airport's history is thus often the very same concrete with a changed name — and airports around the world encounter this repeatedly as the pole wanders. Only near the magnetic poles, for instance in northern Canada, is the compass not reliable at all — runways there are therefore numbered according to true north instead.

On the profile of every airport we track, we show the runway in use live, based on where aircraft have actually been touching down and taking off from in the last few minutes; long-term direction usage is in the Statistics tab. And we draw a closed runway crossed out on the diagram — so you can also tell which strip of concrete isn't currently in use.