Short clips tied to city transport have become a staple of online editing because a couple of seconds can set a whole scene without explanation. The Metro de Madrid clip fits that pattern, circulating on soundboards and in short-form videos where creators want an immediate sense of Madrid, commuting or Spanish city life. Its appeal is practical rather than musical: it is brief, easy to recognise as a metro sound and simple to place over travel footage, memes about rush hour or jokes about getting lost in a big city. That versatility keeps it useful long after its first uploads.