Santalune City (Japanese: ハクダンシティHakudan City) is a city located in the central part of the Kalosregion. It is the hometown of the first Gym Leader, Viola. Route 3 is to the south, Route 4 is to the north, and Route 22 is to the east.
The stone-walled city features brick pathways interwoven between European-style homes and buildings. Many gardens and buildings in the city are decorated with colorful flowers, and the central plaza features a large, Roselia-shaped stone fountain.
The Santalune Gym is the official Gym of Santalune City, whose Gym Leader is Viola and specializes in Bug-type Pokémon.
The Trainers' School is located west of the Gym. Inside, there are four children and an old man. The old man gives the player three X Attacks and three X Defenses. On the marker board in the back of the school is a list of status ailments with descriptions.
Santalune City first appeared in Kangaskhan...Kangascan't, where X and his friends arrived there. After having almost gotten caught by Team Flare in Aquacorde Town, Y presented the group with five rules to protect themselves, but she was interrupted by Shauna before she could say the fifth rule. Viola then showed up, introducing herself as the city's Gym Leader, and offered to help the group with their search for answers, as she was in Vaniville Town at the time of when Xerneas and Yveltal clashed there. While the rest of the group accepted the offer, Shauna, disgusted by her friends violating the rules Y had just presented for them, went off on her own. The others followed Viola to the Santalune Gym, where X agreed to a quick battle against her while Tierno and Trevor helped Y decipher some clues from the photos Viola took at Vaniville. Y then left to look for Shauna, and returned with her just as X won his battle against Viola.
At the night, Shauna sneaked into the room where Kanga and Li'l Kanga were sleeping, and took out Kanga's Mega Stone from her pouch. However, her actions were noticed by Y and Viola, who quarreled with her for a moment, until she suddenly pulled out a sword and tried to strike Y with it, but Viola took the hit to protect her. The culprit for Shauna's odd behavior was soon revealed to be Celosia, who had put Shauna under mind control to steal the Mega Stone. X started pursuing Celosia, proclaiming that he'd fight against her even without Mega Evolution. He was then joined up by Shalour City Gym Leader Korrina, who used her Mega Lucario to help X. After the Mega Stone was recovered, X was able to Mega Evolve Li'l Kanga, who helped Korrina's Lucario to defeat Celosia's Aegislash, forcing the Team Flare Scientist to retreat. Afterwards, Shauna apologized the others for wandering off. Although Korrina was kind enough to give Tierno a pair of Roller Skates, she refused to teach X about Mega Evolution, as he hadn't gone through the appropriate ritual to become a Mega Evolution Successor, and thus, in her eyes, was unworthy to use it. Having made her opinions clear, Korrina then proceeded to storm off.
Santalune City shares several similarities with Viridian City; both cities contain the first Gym the player will encounter on their journey, and both cities connect to three similar routes: Route 22, leading to the badge checkpoints for the Pokémon League; a route leading to the town or city where the player can choose a Kanto starter Pokémon; and a route which leads to a forest named after the city. Incidentally, the internal layouts of both forests are very similar to one another.