The Hogwarts Express departs from Platform 9¾ in J.K. Rowling’s Harry Potter series.
The hidden platform is located at London’s King’s Cross railway station in the books. Young witches and wizards reach it by running through the barrier between platforms 9 and 10. The train then carries students to Hogsmeade station near Hogwarts at the beginning of the school year.
Platform 9¾ is a fictional location, but King’s Cross is a real London station. The platform number uses the fraction three-quarters to emphasize that the magical platform exists between ordinary numbered platforms. This detail became one of the most recognizable pieces of wizarding-world imagery.
The films used a set and filming locations to represent the platform and station scenes. King’s Cross later installed a Platform 9¾ shopping and photo area for visitors, although the actual railway station does not contain a literal magical platform.