Pokémon Ruby and Sapphire/Mauville City

You can do a whole bunch of stuff here, first of all, there is a gym here, which you can battle to get your 3rd badge, in Emerald, you can rebattle this gym after you beat the elite four. You can also get your first bike or you can switch bikes here. There is also the game corner here... Which you can play to win special TMs. Plus, you can get the HM Rock Smash here.

Mauville Game Corner
The Mauville Game corner has lots of TMs here. This Game Corner has Psychic, Flamethrower, Ice Beam and Thunderbolt! This is the only Game Corner in Pokémon Ruby and Sapphire. There is another Game Corner in Mossdeep City for Emerald users.

Mauville City Gym
This Gym specializes in Electric types. It is recommended that you bring a Rock Type Pokémon like which can be found in Granite Cave in Dewford Town.

Trainers

 * Guitarist Kirk
 * Elecktrike and Magnemite


 * Youngster Ben
 * Zigzagoon


 * Guitarist Shawn
 * Three Voltorbs


 * Battle Girl Vivian
 * Meditite