Diglett Cave

Walkthrough
After defeating the Vermilion City Gym, Misty, the Cerulean City Gym Leader, will arrive in Vermilion City and escort you to Diglett Cave. This cave connects Route 11 (just east of Vermilion City) to the earlier inaccessible part of Route 2, being full of just a few Pokemon. Once through and on the other section of Route 2, you will be able to learn the Light Up Technique from one of Professor Oak's Aides. After you have, your Rival will appear and offer to take you to Rock Tunnel (where you will need to use the Light Up Technique).

Wild Pokemon
Standard Walking:
Diglett (85%): Levels 13-18
Zubat (10%): Levels 13-18
Dugtrio (5%): Levels 13-18

Standard Walking - Special Spawns:
Chansey: Levels 13-18


Post Game
Walkthrough
After defeating the Elite Four and starting the Master Trainers Challenge, you will find a couple of Master Trainers within Diglett Cave. In total, there will be two Master Trainers to defeat.

Trainers
Hiker Collin (Master Trainer): Level 70 Diglett
Hiker Dexter (Master Trainer): Level 75 Dugtrio