Cerulean Cave

43 Pokémon can be caught at Cerulean Cave in Kanto — highlighted on the map below.

Originally introduced as the Unknown Dungeon, Cerulean Cave sits in the northwest corner of Cerulean City and shelters some of Kanto's strongest wild Pokémon, with Mewtwo lurking in its deepest chamber. The Pokémon League controls access, admitting only trainers who have entered the Hall of Fame or met equivalent milestones. In Generation II the cave lies collapsed, leaving only the Berserk Gene near its former site, but it is rebuilt in HeartGold and SoulSilver, where a Mew brought inside grows uneasy sensing Mewtwo.