Route 8 (Japanese: ８番道路Route 8) is a route in western Kalos. It consists of two different paths. The upper cliffside path connects Ambrette Town and Connecting Cave, while the lower seaside path connects Ambrette Town and Cyllage City. The route is also known as Muraille Coast (Japanese: ミュライユ海岸Muraille Coast).
The upper section of Muraille Coast is a rocky mountain road, whose cliffs offer a clear and magnificent view to the sandy beach and ocean below. Despite the rocky environment, tall grass and colorful flowers can be found growing here. Many ledges restrict the player's movements here, although some of them can be circled around. Due to the high altitudes present on the route, Sky Trainers tend to be present on the cliffs.
The lower section of Muraille Coast can be accessed from the bottom floor of the Ambrette Aquarium, and it consists of a bright, sandy beach and a slice of ocean. It is full of not only Water-type Pokémon, but also water-themed Trainers, such as Swimmers and Fishermen. A Mago Berry tree is growing in the southern area of the route. Many rocks can also be found across the beach, especially near the south end. Some of these rocks can be broken with Rock Smash. One such rock is blocking access to a Trainer Tips sign, which will notice the player being able to use Rock Smash to reach it.
A female Swimmer will prevent the player from going through a certain point of the beach until they've obtained a Fossil from the Scientist in Glittering Cave, after which she'll give the player a Dowsing Machine, making locating hidden items a lot easier.
Route 8 appeared in An Undersea Place to Call Home!, where Ash and his friends briefly stopped there to relax before Ash's Gymbattle with Grant. While fishing to pass the time, Ash hooked a Skrelp, which attacked him and his friends, as it thought that they were its enemies. During the commotion, Pikachu got hit by Skrelp's Toxic and was badly poisoned. The group then met Eddy and Lindsey, who healed Pikachu before introducing themselves as underwater archeologists. They explained that a sunken luxury liner named the S.S. Cussler could be found near Muraille Coast, and they were planning to find it and get the treasures that had supposedly sunken with it. Through a fair game of chance, Ash and Serena were chosen to join Lindsey in diving down to look for the sunken ship with a submarine, while Clemont and Bonnie stayed on the surface.
The divers eventually managed to find the sunken ship, which, as they found out, had become a home for numerous Water-type Pokémon, including the Skrelp from before and a group of Dragalge. Unfortunately, Team Rocket had overheard the story about the treasure, and had used their Magikarp submarine to dive down to the ship as well. They managed to find the safe containing the treasure and blasted it off of the ship, causing the parts of the ship that were still filled with air to flood and almost resulting in the entire ship collapsing. However, with the help of Lindsey's submarine, the Dragalge were able to stop the flooding and prevent the ship from collapsing completely. Meanwhile, Team Rocket, escaping with the safe from the ship, got caught up in a series of currents that had briefly disappeared earlier and now reappeared, and were sent blasting off by them, accidentally dropping the safe back into the sea in the process.
In PS574, Celosia led an operation to retrieve Xerneas so that Team Flare may use its life energy to power the ultimate weapon. Due to Team Flare lacking the manpower necessary to move Xerneas, Celosia had her Aegislash mind-control people who attempted to flee Vaniville Town when Xerneas and Yveltal battled against each other. Upon learning of this plan, X and his friends confronted Celosia, Essentia, and Malva in order to free the kidnapped people. With the assistance of Korrina, Gurkinn, and Diantha, X and his friends succeeded in freeing the people kidnapped from Vaniville Town, but were unable to prevent Xerneas from successfully being taken to Team Flare's headquarters.
In PS581, Malva revealed that Yveltal had went into its dormant cocoon form under the ground beneath Xerneas's tree form. By traveling under the ground during her battle against Diantha, Malva had been able to find and catch Yveltal.