He may go to a small wizarding village in France. The French wizarding community has a rich history and unique magic. Harry could immerse himself in learning French magic, make new friends among the French wizards and witches, and enjoy the laid - back lifestyle in a charming French village, far from the reminders of the war in England.
He might go to America. The American wizarding world is different from the British one. There are different magical creatures and a different magical culture. Harry could go there to start anew, maybe help out at Ilvermorny or explore the magical wilderness of the States.
Perhaps he leaves to explore the Muggle world. Harry has always had an interest in Muggles. After the war, he realizes he wants to experience life without magic for a while. He could go to university in a big city like London, study a Muggle subject like history or literature. He'd make new Muggle friends and try to fit in, all while still having his magical abilities hidden, which would add an interesting dynamic to his new life.
Hermione might go with him. She's always been by Harry's side, and she would likely follow him out of loyalty and also because she might see the value in whatever mission or journey Harry is embarking on. She could provide the intellectual support and research skills that Harry needs.
There's a chance he meets a group of nomadic magic - users. These are people who travel across the universe in search of new sources of magic. They could introduce Harry to different forms of magic that are not based on the traditional elements like fire, water, earth, and air that he's used to on Earth. Instead, they might use things like starlight or cosmic energy as a basis for their spells.
Perhaps Harry meets magical creatures that are rarely seen by wizards. Since he is out exploring after the war, he might stumble upon a group of centaurs who have their own unique wisdom about magic and the future. He could also encounter veelas, and through his interactions with them, learn more about the different cultures within the magical world. There's also a chance he meets other young wizards who are on their own adventures, and they form a sort of traveling group together.
He could meet other famous wizards from different countries. For example, he might run into Nicolas Flamel, who has been traveling around the world. Flamel could share with Harry some of his vast knowledge of alchemy and magic that has been passed down through the ages. This encounter could give Harry new insights into magic and its potential uses.
The plot could develop with Harry secretly studying dark magic texts in the restricted section of the library. He might start to have strange dreams or experiences related to the dark magic he's exploring, and he has to be very careful not to get caught by Filch or the teachers.
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One possible storyline could be that Harry leaves to explore the wizarding world outside of Britain. He might go on a journey to discover new magical creatures and spells in far - off lands. Another could be that he leaves to find a place of peace and solitude, perhaps in a hidden magical enclave, to deal with the trauma of the war. And he could also leave to train young wizards in secret, away from the public eye, to ensure they are well - prepared for any future threats.
They might go to France. France has a rich wizarding history and a beautiful wizarding community. The Beauxbatons Academy is there, and they could explore the magic related to it. There are also magical places like the French Ministry of Magic which would be interesting for them to visit.
The story could develop in a way that Harry goes through a period of self - discovery. Without the Gryffindor identity, he has to re - evaluate who he is. He might explore different kinds of magic that Gryffindor house never encouraged. This exploration could lead him to new powers and a new understanding of the wizarding world.