Though its design varies between games, Peach's Castle is usually a wide gray-brick building with a red shingle roof, four spired towers supporting the corners, and a fifth tower on top. On the front balcony is a stained-glass portrait of Princess Peach, created by the citizens of the Mushroom Kingdom to bring them comfort when she is absent. The castle is sometimes surrounded by a moat within a hilly grassland area near Toad Town.
Peach's Castle first appeared in Super Mario 64 as the hub world, containing enchanted paintings, objects, and entrances that lead to various courses. Mushroom Castle from Super Mario RPG may be a prototype of this location. It then appeared in various spinoff series before a main-series return in New Super Mario Bros., in which Lakithunder attacks it to distract Mario and allow Bowser Jr. to abscond with Princess Peach.
Several games, most notably Paper Mario, Super Mario Galaxy, and New Super Mario Bros. U, have seen Bowser taking over Peach's Castle. The former two games also involve Bowser lifting the castle into space. In the Paper Mario iteration, Bowser's Castle has been built underneath to facilitate this plan; this version of the castles also made a cameo reappearance near Rainbow Road in Mario Kart: Super Circuit.