Another first to Pokémon X & Y is rideable Pokémon. In a variety of areas, you will have the ability to ride certain Pokémon. These Pokémon have special abilities within the area that they can be riden, but unfortunately you cannot ride your own Pokémon. Click the image for a larger version

Location	Pokémon	Special Ability	Picture
Lumiose City	Gogoat	In Lumiose City, there are special boards where you can pay $200 to go through a tour of Lumiose City on Gogoat. You have no control over Gogoat
Route 9 Vaniville Town	Rhyhorn	In Route 9, you have to ride a Rhyhorn to get over particularly rocky terrain. It can smash rocks that are blocking the path
Route 12	Skiddo	In Route 12 there is a farm full of Skiddo. When you ride Skiddo, you can jump backwards over ledges and ride really fast.
Route 17	Mamoswine	In Route 17, you have to ride a Mamoswine to get over particularly snowy terrain. It can smash rocks that are blocking the path
Kalos	Lapras	If you teach Surf to Lapras and use it, you will be shown to be riding the Lapras rather than the conventional surfing image