Hogwarts the Hogwarts Express that students take at the start of each school year. Students board the train from the also fictional and hidden Platform 9¾ at King's Cross station in London. The train arrives near Hogwarts, some time after nightfall. From there, first-year students are accompanied by the "Keeper of the Keys, Game and Grounds" (which was Hagrid during the first novel) to small boats, which magically sail across the lake and get them near the entrance of Hogwarts. The older students ride up to the castle in carriages pulled by creatures called Thestrals. When the first-year students initially arrive
Hogwarts "Half-Blood Prince" Harry used the Room of Hidden Things to stash his copy of "Advanced Potion-Making", describing it as the size of a large cathedral and packed to overflowing with items hidden by Hogwarts inhabitants over the years, such as old potions, clothing, ruined furniture, an old tiara (which happened to be one of Voldemort's Horcruxes), or books which were "no doubt banned or graffitied or stolen." He later realised that Draco had been using the room in that state to hide and repair the Vanishing Cabinet to use it to smuggle Death Eaters into Hogwarts. Ironically, while Harry tries