Route 21 (Japanese: ２１番水道 Water Route 21), known as Sea Route 21 in Generation I, is a water route located in southwestern Kanto. It connects Cinnabar Island in the south to Pallet Town in the north.
How do I get to Route 21 in Pokemon?
Route 21 is the water route that connects Pallet Town to Cinnabar Island. One of the ways to find it is by backtracking long forgotten areas (in this case Pallet Town) after obtaining the Surf ability. Use Electric and Grass Pokémon to breeze through this route.
How do you get to Pikachu in Cerulean City?
Keep Moving East To Reach Cerulean City. The travel from Mt. Moon to Cerulean City through Route 4 is not that long. Keep heading east until you reach the city.
Route Location
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Mt. Moon After Pewter City and before Cerulean City.
Route 21 After Saffron City and before Mt. Cinnabar / Cinnabar Vocalno.
Mt. Cinnabar / Cinnabar Volcano Can be found using Route 21.
Route 22 The Route west of Viridian City and before Victory Road.