No Underground Path is in Vermilion City. There is one north of the city that leads to Cerulean City.
Go though the underground path in celebruen city.
Vermilion city is south from Cerulean city to get there though you need to use the underground path.
Its south from Saffron City now you can't go to saffron city because its blocked to reach vermilion city you need to go through the underground path on the route below cerulean city then after going through the path continue south to reach Vermilion City.
After getting the 2nd badge go south from cerulean city and use the underground path to continue your journey south to reach vermilion city.
There is a path between Cerulean and Vermilion, and between Lavender and Celadon.
Well you go through an underground path and the gym leader you need to know CUT
Celadon city to go there go to cerulean city and go right theres a tree use Cut on it then continue east until you reach a cave this is rock tunnel go through here and you will end up in lavendar town if you go west from here you will notice a underground path go through the path and you will eventually arrive in celadon city.
The underground path leads you to a city or town that you currently can't go to due to a security guard all you need to do is go to the other side and go upstairs you will appear near a place you previously couldn't go to. Also in the path you can find secret items.
in toronto ---- Montreal's underground city is the largest underground complex in the world.
there are two snorlax on Pokemon fire red one of them is too the right of vermilion city before the fishing trail, and the other is too the left of celadon city before the bike path. both can be caught with great balls.
. underground path in Celedon city
You cannot go unlock the Underground Path in HG/SS because you don't actually need it, since you can go through Saffron City.