Remiem Temple is an optional area accessible from the Calm Lands, after clearing the first Chocobo Training course. This allows you to ride a chocobo on the Calm Lands, so head up the ramp near the entrance to the Calm Lands and look for a feather on the right side. Interact with it to fly to the entrance to Remiem Temple. Once in the area, go to the right side and you will find a chocobo. Talking to the chocobo will allow you to start the race, where you need to make it to the bottom. Along the way, you will find chests and if you open a certain number, while still winning, then you will get prizes. For more information on how to easily get all 5 chests and still win, visit the Remiem Temple Walkthrough page.