A naturally formed underground tunnel. Because it has not been developed, it is inky dark inside. A light is needed to get through.FRLG A dark tunnel that begins in Lavender Town and comes out in Cerulean City.HGSS A large natural tunnel. It's pitch black, so a light source is required.PE
The Rock Tunnel (Japanese: イワヤマトンネルRock Mountain Tunnel) is a naturally formed underground tunnel. Since it has not been developed, it is pitch black inside. A light of some sort is needed for travelers to find their way, so it is recommended that Pokémon Trainers bring along a Pokémon that can use Flash outside of battle.
Rock Tunnel is the only alternative route to Lavender Town, as the two other routes have been rendered inaccessible by a slumbering Snorlax and the Saffron City gatekeepers. The cave has two separate floors, both of which are roughly the same size. There are many Trainers within the cave, there for the fun of exploring, training, or are simply lost in the darkness.
Route 10 leads from Cerulean City to Rock Tunnel. At the northern entrance of the cave is a convenient Pokémon Center. The roof of the Kanto Power Plant can also be seen from here (excluding Generation III). The southern entrance exits onto the remainder of Route 10, leading to Lavender Town.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
A colored background means that the Pokémon can be found in this location in the specified game. A white background with a colored letter means that the Pokémon cannot be found here.
One of the Poké Maniacs in the tunnel makes a reference to Mobile Fighter G Gundam, saying "Pokémon Fight! Ready, Go!" prior to battle. Official Gundam Fights in the series began with both participants declaring "Gundam Fight! Ready, Go!"
Rock Tunnel is the only one of Kanto's caves to appear in each of the first four generations with the same background music.
Hornblende biotite granite is present in Rock Tunnel, as revealed in Steven Stone's house.