The home of the first Jedi Temple and the place Luke Skywalker has chosen for self-exile is a real place anyone can visit. Skellig Michael, an island off the coast of Portmagee, is Ahch-To. Any shot panning over the island in the movie is based on real camera footage. When Rey tries to give Luke his lightsaber and he casually tosses it aside, that’s Skellig Michael.
Skellig Michael is a remote wildlife preserve (read more about that here), so production only filmed on the island for two days each for
When Rey rudely cuts a rock in half with the lightsaber and upsets the Caretakers (they are probably not the galaxy’s biggest Rey fans), it’s on Skellig Michael and it’s not any normal rock. It’s the Wailing Woman. The rock is so named by early lighthouse keepers because the silhouette reminded them of a lonely figure.
The infamous green milk scene was not filmed on Ahch-To. The thala-siren, a.k.a. space sea cow, was flown in by helicopter to Dunmore Head. You can walk out to the rocky outcrop where the puppet was placed; it’s accessible from Slea Head Beach. You won’t find a paved path, but my completely out of shape self was able to make the hike up the hill and out to the location. Take a cut-out of the sea cow’s head with you for a quality photo opportunity.
Dunmore Head’s craggy coastline made an ideal place to hide Luke Skywalker’s X-wing. The ship itself is CGI, but the location where it’s nestled is real and you can look down from the top of the hill and imagine the ship resting in the water.
They took the set down after filming because nature would have swept it away, but you can still walk out to the edge and imagine you’re on Ahch-To. Or if you want to visit some accessible beehive huts that are real but were not used for filming, stop by a place on the Dingle Peninsula called Hold a Baby Lamp and Beehive Huts. You can indeed hold (and maybe feed!) a baby lamb and tour intact, impressive Fahan beehive huts built over 1,400 years ago.
Those locations were the only ones I saw firsthand, but production utilized a few other spots in Ireland. The Millennium Falcon landing on Ahch-To was filmed on Malin Head. The place where Luke leaped from cliff to cliff to spear a fish? That landscape can be found at Brow Head. And finally, the spot where Rey takes her dive into