In pokemon red, where is the rock tunnel to get to Lavender town?

I can't seem to find it. I thought it might be diglets cave, but that doesnt seem to be it.

Any one help?

Maybe is there something I have to do before it is shown?

In pokemon red, where is the rock tunnel to get to Lavender town?
Go to Vermilion City, where misty is rhe gym leader, go east, cut the small tree blocking your way. Follow this untill you are at the cave. you can aslo get zapdos in this direction after getting surf. Just find the body of water buy the cave and surf untill you reach the power plant, at the end is zapdos.
Reply:havnt played 4 ages might be the tunnel near the power plant you will need flash i think?
Reply:The Tunnel should be east of Vermilion City (Routes 9 or 10)