In Pokémon Red, Blue, and Yellow, you need to defeat the Elite Four.
In Pokémon Fire Red and Leaf Green, you need to defeat the Elite Four and enable trade with Ruby, Sapphire, and Emerald. To do that, after you beat the Elite Four, obtain the Ruby and the Sapphire in the Sevii Islands, and take them to Celio in the Pokémon Center on One Island.
In Pokémon Heart Gold and Soul Silver, you need to beat the Elite Four, and then beat all eight of the Kanto Gyms.
Cerulean Cave, outside Cerulean City
In Ceurelean City Cave there is Mewtwo.
Cerulean Cave, nor Cerulean City, was not in Pokemon Emerald. In RBY, it opens up after beating the Elite 4.
The cerulean cave is behind that man that says u need all badges to get through. It is in cerulean city
uh...... if you didn't go into the dark cave in johto and the cave east to cerulean and north of the electric plant. P.S don't mistake the cave in cerulean city. not the cerulean cave!!!!!!!!!!!!!
Cerulean cave located near cerulean city.
you have to beat the elite four, and get the national dex. then go to cerulean city, go past the nugget bridge, and surf on the water. there is a cave,and its cerulean cave
The Cerulean Cave is in Cerulean City. You have to surf from a place around Cerulean Cape down to the Cerulean Cave. The Cerulean Cape is north of Cerulean City across the bridge.Go to the north end of the nugget bridge then left down the grass and follow the mountain to it. Btw you'll need flash and you can find Mewtwo in it.
inside cerulean cave near cerulean city.
mewtwo is in cerulean cave. the cave in in cerulean city, where misty's gym is. mewtwo in hard to catch, though.
You can find the Cerulean Cave in the northwest corner of Cerulean City in Kanto in Pokemon LeafGreen. The cave contains the Pokemon Mewtwo.
The Cerulean Cave is located in the west part of Cerulean City. If you head north, you will notice a water way to the left of the bridge. Surf on that waterway and you will eventually reach Cerulean Cave.