Commonly seen painted on platform edges and heard on voice-overs when travelling on London’s Underground, the phrase “Mind the gap” refers to being careful when boarding a train of the gap between the train and platform.

This is especially the case when on platforms which aren’t necessarily straight such as at some stations on the London Underground, a fact which can increase the gap between trains and the platform.

The phrase was apparently first adopted on a pre-recorded recording on the Underground in 1968. It can now be heard on live and recorded announcements at stations across London.

There have been some famous voices which have uttered the line on the Underground – among them King Charles III and Queen Camilla around the weekend of his coronation.

While the phrase can now be heard on various public transport systems around the world, it is still heavily associated with London.

It’s also been heard in everything from an Avengers film, video games including Halo and even in music (Yintan’s single, Mind the Gap, for example, features one of the London Underground recorded announcers, Emma Clarke).