The magical train platform in J.K. Rowling’s Harry Potter series is Platform 9¾.
Platform 9¾ is the hidden departure point for the Hogwarts Express at London’s King’s Cross station. Young witches and wizards reach it by running through the barrier between platforms 9 and 10. The Hogwarts Express then carries students to Hogsmeade station at the beginning of each school year.
The platform is central to the opening and closing journeys of the school term. Harry first learns how to find it when the Weasley family helps him at King’s Cross. The location also appears in the epilogue, which is set many years after the main story.
King’s Cross later installed a tourist sign and luggage trolley inspired by the fictional platform. The attraction became a popular Harry Potter landmark, even though the real station’s platform arrangement does not exactly match the books’ description.