Yes. The Secret Key is needed to open the Cinnabar Island Gym. The Secret Key can be found on a table in the northwestern room of the basement.
you got to go to the mansion in the city and the key should be at the very bottom floor.
The Celadon Mansion is the large building by the Department Store and Pokemon Center.
No you find it in Pokemon mansion.
its to the left of the pokemon gym on cinnibar island
In the bottom floor of the Celadon Mansion.
In the house you jerk!
its inside the mansion
the secret key is in the Pokemon mansion - Celadon city basement
you go in the Pokemon mansion and the gyms key is some ware in there.
The basement.
u can find it in Pokemon mansion.
You get the card key which lets you open the gym which is locked.
You get the card key which lets you open the gym which is locked.
Get the key from the basement of the mansion next to the gym.
u have to find the key in the Pokemon mansion i think
you got to go to the mansion in the city and the key should be at the very bottom floor.
I'm not sure about leaf green but on firered it's in the basement of the poke mansion. I'm thinking it should be the same since firered and leaf green are so similar.