How can you get to cerulean cave?

Relevant answers:

What is in the cave in cerulean?
I know that on pokemon blue there is a mewtwo in the cave at cerulean, as for leaf green or fire red I don't know but I would guess that there is a mew or some other sort of rare pokemon inside
How do you you get to cerulEAN CAVE?
Its in the northern part of Cerulean City. But you can only get there from route 24 by using surf. Also, in order to enter, you have to have all 16 gym badges and solve a maze to get to Mew2
What do you do after the cerulean cave?
Turn off the game and get a girlfriend.
How can you get into the cerulean cave?
you gat all kanto badges
How do you get in the Cerulean Cave?
1.Answer.To enter the Cerulean Cave you must first beat the Elite Four, in FR/LG you must also complete the Sevii Island quest to restore the Network Machine. In cerulean city, its the cave across...