You defeat the trainers and the gym leader, Misty. Electric attacks are best for this gym.
if you mean on the bridge in cerulean city ,after you have defeated the man their you have yo check the rubber rings at the end of the cerulean gym
You must go and battle Misty. Once you defeat her, she will give you a badge. You have then defeated the gym.
Listen, DON'T us charmeleon in the Gym. Catch another Pokemon, I was able to defeat it with out mine.
The Cerulean Gym (Japanese: ハナダジム Hanada Gym) is the official gym of Cerulean City. It is based on Water-type Pokémon. The Gym Leader is Misty.Trainers that defeat her receive the Cascade Badge.Other known members include Swimmer Briana, Swimmer Parker, Swimmer Diana, Swimmer Luis, Picnicker Diana, and Misty's sisters Daisy, Lily and Violet, who were the leaders in the anime until the Advanced Generation.
In the Cerulean Gym
To obtain the Cascade Badge you will need to defeat Misty the Cerulean City gym leader in a pokemon battle.
in the GYM .
in cerulean city
Lavaridge
Go in the Gym where misty would be the pool in front of you will have it in it.Mr.Seidschlagyou must find the secret part in the cerulean city gym
In Pokemon Heart Gold and Soul Silver, after you defeat the rocket grunt, return the piece back to the Power Plant. Then, you will receive a TM, and then you can finally battle Misty at the Cerulean Gym.
at the top of Cerulean Cape with her boyfriend.