You may have noticed the large painted numbers (or alphanumeric in some cases) on either end of the runways. Have you ever wondered what those represent and why there are a maximum of two numbers ...

Every runway in the world is numbered... twice. These two numbers are closely linked to a shifting magnetic north, but are essential for airports to direct traffic through all the different runways.

AUSTIN, Texas — Flying in and out of Austin’s airport may look different for people who choose the window seat and have an eagle eye. An improved runway, now numbered 18R/36L, opened on Thursday ...