Vermilion City Gym
Description Of Vermilion Gym:
Now that you have the move Cut, you can finally battle the Vermilion City Gym. The Vermilion Gym is home to Leader Lt. Surge, an Electric-Type Pokemon User. His Gym is pretty tricky, with you having to find two consecutive switches in the trash - they are right next to each other - before you can battle Surge.
Since his Gym is built this way, odds are you'll have to battle all three trainers spread throughout the gym:
Sailor - Level 24 Magnemite
Rocker - Level 20 Voltorb, Level 20 Voltorb & Level 20 Voltorb
Gentleman - Level 22 Voltorb & Level 22 Magnemite
After finding the two switches, you can face Surge. If you have taught one of your Pokemon Dig with the TM you received in Cerulean City, the Gym Battle will be a breeze.
Lt. Surge's Pokemon: Level 28 Raichu
After you defeat Lt. Surge, you'll receive the Thunder Badge and TM24 (Thunderbolt). You will also be alllowed to use HM02 (Fly) outside of battle.