Visiting this zone counts for the "Well Traveled" achievement.
As it is very easy to get lost in the Temple of Enlightenment, a detailed guide is highly recommended. There are numerous lifts, as well as many movable platforms. It is split into two main sections. Those being the inside and outside of the temple.
Location: You will only be able to access this location after you have gained the White Boa and the submerge action for the Nautilus. It is located on the south-east continent past the Hyper-Currents. You will need to take the White Boa around to smash through the ice. Once through, deploy the Nautilus and go to the ocean floor. There will be a small underwater cave, go through it and surface at the other side. Then when you land at the shore you will be able to travel to the Temple of Enlightenment.
This is a very good place to level up, as the enemies here grant you a lot of XP. The most XP is granted by the Hellish Kelolons, who only appear inside the temple. They are not to be mistaken with the Black Kelolons, who also appear outside but grant less XP.
These two Kelolons look very similar, but can be distinguished easily by the amount of HP they have:
The outside of the temple is where you can find the two Gems that are needed to summon the platform that will take you to the Boss area. Each Gem can be found in the middle of four pillars with green light flowing from their tips to the Gem. One Gem is on one side of the temple the other is on the opposite. In order to get these Gems you will have to send up any lifts that you find in the outdoors area. Sending up the lifts involves standing on a tiny gray platform, and using the ball of light that appears there. Ignoring the lifts will result in a long trip back down the temple. Be warned.
If you get lost and can't find the two Gems, look around the outside areas of the level for ladders that blend in with the walls. There is one for each of the areas above the gems.