Go through doors
You have to go into the pokemon mansion, find your way through it, and pull a switch and the gym will open.
You can ether find your'e way or use an escape rope.
you have to work your way through the Pokemon mansion and go out the right door while using the correct switches its and the very end of the Pokemon mansion
In Pokemon Fire Red and Leaf Green, it is possible to go up the stairs in Celadon Mansion if you enter through the back. All the way at the top of the mansion, the player can find an Eevee.
you can use the statues through out the building to open stuff and there will be a place where it is all black you go walk into that then find your way through to the key
You will need to work your way to the basement in the Pokemon Mansion, you will then find the Key.
their is a mansion on cinibar island. You go through the mansion pressing buttons that look like nidokings on your way through. at the end of the mansion there is a key that opens the gym
go to cerulean city and go behind the Pokemon mansion and enter through the back, go all the way to the roof and go into the only room and on the table will be a pokeball with a lvl 25 eevee! Eh-hem. It's CELADON city not cerculen and its the celadon mansion not the Pokemon mansion
You can't catch eevee as a wild pokemon, but you receive on the roof of the Celadon Mansion(you have to go through the back way, going through the front will take you the wrong way)
The best way to get into the secret rooms in the Pokemon mansion is to find a cheat code for the Pokemon game and install it before playing. You should then be able to easily get into the secrets rooms on floors 2 and 3.
you have to go into the pokemon mansion on cinnabar island and navigate your way around there untill you find the key
not the top secret onesYou can also hack the game with the walk through walls code, but there's nothing behind the doors.