ummm, there are no obstacles in he way of getting there, just head north from saffron. (pewter city is the one that's hard to get to.)
it is north of cerulean city
Get a better game :)
you go to cerulean city and beat misty.
in cerulean city
head East of Cerulean City then surf a little.
By walking there from Saffron City or through Rock Tunnel from Cerulean City.
it is in cerulean cave
mewtwo
just go to the cerulean city cave.
he is in a cerulean cave i beleive
in cerulean cave
Cerulean Cave