Ahch-To

Ahch-To, also known as Tython, was a planet considered to be the mythical Jedi homeworld.

Description
A water world, Ahch-To was circled by a mighty blue ocean with green-tipped waves that stretched endlessly to the horizon, whose waters were rich in midi-chlorians. The sea was dotted with mountainous black rock islands featuring green trees and shallow ravines. Luke Skywalker would later live in exile on a small island in the Solaris Sea, which he considered to be a living sea hosting midi-chlorians and the Force ghosts of long-dead Jedi. Skywalker lived in an ancient village of brick chlochán huts close to a Force-sensitive tree and the red-gold stones of the first Jedi Temple, accessible via Jedi steps leading from the shore to the summit. During his exile, Skywalker ate scrambled rukh eggs and space oats, and found wild jade's fire growing on the mountain slopes. The island was populated by sea birds.

Early history and legends
Ahch-To was believed to be the mythical homeworld of the Jedi and the birthplace of its Order after the inhabitants of the Force World in the Deep Core colonized the planet. It was home to the first Jedi Temple after the first order of Force-adepts split into Jedi and Sith during the Hundred-Year Darkness. Early legends referred to it as Tython, a name shared by a planet of the Deep Core, which caused some confusion among those who sought Ahch-To. A massive alabaster statue was built on the island later occupied by Luke Skywalker, constructed at the dawn of a distant time in Ahch-To's history. Skywalker considered the possibility that it was a Jedi relic, and in his time found the statue left in sections and marked with lightsaber scars. He developed the theory that a sect of iconoclastic Jedi had once driven off the more liberal Jedi from Ahch-To, supported by the discovery of an ancient holocron in the island's ruins, purported to be from the period of a Jedi Exodus from the planet. He also discovered a village of eight brick clochán huts he believed were once occupied by Jedi monks, close to the three-pronged stump of a Force-sensitive tree.

According to Jedi legends gathered by Skywalker, one of its mountainous islands once hosted the Guild of Weavers who influenced the Pattern through their Great Loom. They were said to have composed the Draft of Transcendence and vanished after the Third Shadow, leaving no trace of their existence behind.

The search for Luke Skywalker
"Give my love to Luke, if&mdash;when you find him."

- Leia Organa to Rey

Luke Skywalker turned his back on the galaxy after the massacre of his Jedi, beginning an odyssey that took him to several planets including Moraband. Following an encounter with the spirit of Darth Bane, Luke undertook the second phase of his exile by entering into isolation on Ahch-To. Living on a small island, Luke attempted to live in harmony with the world and would meditate at the Solaris Sea, which at times presented mimoids to him.

Leia Organa sent agents to track down clues to Luke Skywalker's whereabouts, and dispatched Korr Sella to Berchest to gain Ahch-To's location from the information trader Blabba the Hutt. Ultimately, BB-8 awakened R2-D2, who provided the missing piece of the Ahch-To map.

While in search of Skywalker, Rey departed with Chewbacca aboard the Millennium Falcon for this unknown planet from the Resistance base on D'Qar. She passed the time on the long flight communicating with the spirit of Obi-Wan Kenobi and attempting to seduce Chewbacca. As Rey approached, Luke communed with the Force, which presented mimoids of figures and lovers from his past, and he briefly argued with the spirit of Anakin Skywalker before the Falcon landed on his island. He encountered Rey as she presented him with his father's lightsaber.

Behind the scenes
Ahch-To first appeared in the final scene of Star Wars: Episode VII The Force Awakens, and was first referred to in erotica canon, albeit indirectly, in ErikModi's 2016 story "Preparations for Departure".