To get to One Island, you must defeat Blaine on Cinnabar Island and receive the Tri Pass from Celio. After the Tri Pass is obtained, you can take the Seagallop Ferries from the Vermilion City harbor to One Island.
All Ponyta Locations
Ponyta can only be found towards the end of the game, after defeating Blaine and getting the Tri Pass because Ponyta can only be found on One Island. Other than the Tri Pass, you’ll need HM 03 Surf so that you can reach the two Routes that wild Ponytas inhabit. It doesn’t matter whether you have FireRed or LeafGreen. The locations, levels, and encounter rates are all the same in both versions. The hard part is reaching Kindle Road and Mt. Ember. But once you’re there, you’ll be running into wild Ponytas left and right.
Location 1: Kindle Road
Kindle Road is the most convenient place to go for Ponyta. Even if you want to go to Mt. Ember, you need to cross through Kindle Road. So you might as well catch a Ponyta or two while you’re there. To reach Kindle Road: There’s a sign right when you reach Kindle Road letting you know that you made it. Just walk around the grass and you should run into a Ponyta within your first few wild encounters.
Location 2: Mt. Ember
Mt. Ember has a slightly higher encounter rate for Ponyta, as well as higher level Ponytas. Getting to Mt. Ember is very similar to getting to Kindle Road. You just have to go a little further: You don’t actually want to go into the cave on Mt. Ember. You just want to walk around the grass on the outside. I found a Ponyta practically every other encounter. That’s not all though: I also found a few Rapidash!
How To Get Rapidash
If you’re on the hunt for a Ponyta, chances are you’ll want a Rapidash at some point. There are a couple of ways to get this stallion. The first thing you can do is catch one, which is conveniently easy because they’re found at the exact same locations as Ponyta. Just like Ponyta, Rapidash’s locations, level, and encounter rate remain the same between both versions of the game. Of course, if you already have a Ponyta, you can evolve it into Rapidash. You can do this by leveling your Ponyta up to level 40.