Get to Celadon City via the Underground path and buy some drink on the highest floor of the Dept. Store from the Vending Machine.
In Pokemon red and blue version, go to the department store in celadon city, buy a drink from a vending machine, and give it to one of the guards around saffron city. They will share the drink with the other guards, and all will give you access. In fire red and leaf green, you follow a similar procedure, but instead of getting a drink from the vending machine, talk to the lady on the first floor of the Pokemon mansion (also in celadon city), and she will give you tea for you to give to the guards, instead.
1st city
there is nobody in the way
cerelean city
The Pokemon Fan Club is in Vermilion City.
if you meen in Cerulian city you need nationalpokedex, to get that yo need to take the Pokemon league and get 60 Pokemon
It is not water it is tea and you get it by going to celadon city and getting it from a old lady
Fuchsia city.
in saffron city
from Sabrina in saffron city
Vermillion City
Vermilion city.