Diglett Cave
Description Of Diglett Cave:
After defeating the Vermilion City Gym, it's only logical to head through Diglett Cave just east of the City to get back to Route 2. Diglett Cave is a relatively simple cave, with no items or trainers and only two Wild Pokemon.
Wild Pokemon In Diglett Cave:
Walking:
Diglett - Levels 15-22 - 95% Appearance Rate
Dugtrio - Levels 29-31 - 5% Appearance Rate