Platform Nine And Three Quarters

From Concordances and Characters

Platform Nine And Three Quarters is the platform at King's Cross Station in London where the Hogwarts Express departs from. It is hidden from Muggles by powerful magic, and even wizards cannot see it from within King's Cross proper. It can be reached (by wizards, at least) by passing through a seemingly solid barrier between Platform Nine and Platform Ten. At that point, the platform itself is perfectly visible, and the entrance is visible as a wrought iron archway bearing the legend "Platform Nine and Three Quarters". The platform itself is capacious enough for dozens of Hogwarts students and their family.