1 Work by LadyVana in Harry Potter - J. K. Rowling
Arthur has slept in Avalon, the otherworldly place just beyond the reach of magic for all but Merlin and his chosen, recovering from the injuries sustained in the battle at Camlann. Years have passed and times have changed and Hogwart’s school of Witchcraft and Wizardry has taken it’s place on the edge of the Lake of Avalon, unknown to modern witches and wizards. The world is in need of the Once and Future King to protect Albion again but to do that the immortal Merlin, the man that has learned to live backwards, must be there and he is nowhere to be found. It is now the job of Merlin’s Chosen. Only, Harry Potter thinks he’s going mental.
This is based on the mountains that are around the movie version of Hogwarts and the lake that Merlin takes Freya to in season 2 episode 9.