The Harry Potter Trading Card Game Adventures at Hogwarts Expansion (or simply Adventures at Hogwarts, for short) was the fourth set of cards of Harry Potter Trading Card Game, and the third expansion to the base set. It was introduced in June 2002, and like the base set, the Quidditch Cup Expansion, and the Diagon Alley Expansion, its 80 cards were based on scenes from the Harry Potter and the Philosopher's Stone book by J. K. Rowling.