Feywild

The Feywild is a mirror plane of the material plane. The mirror plane is geographically similar, but not an exact copy. The creatures, structures, and geography is notably more beautiful and exotic. A mundane Oak tree within the Material plane may have sprawling limbs and covered in an assortment of buds and blooms in the feywild plane.
Arcane magic within the feywild is more freely wielded and stronger compared to the material plane. The feywild itself was created by primordials, powerful beings compared to gods. The primordials considered some things of the material too bright, colorful, or magical for the material plane. They ripped these aspects from the plane to form a new plane. 
Within the plane created the Eladrin, an ancient elven race created by the blood of gods. These aladrin created powerful kingdoms and citadils to rule and embrace the feywild. Over several millennia of peace, came conflict with the dragons. Hoping for help from the more primitive life on the material plane, the eladrin connected the two worlds through rifts. The Eldarin began to breed with the nearly identical elves of the material plane.
More and more fled the feywild leaving remnants of their great kingdoms. The ties of these two planes became looser only being tied together by the arcane weave. The weave connection creates rifts between the two planes. The rifts are not always present, but may appear when strong magic is present. 
These rifts can be innately sensed by those with fey ancestry as they feel a tie to their homelands. Some of these fey use these ties to increase their magic prowess calling on these ancient ties to the weave and sources outside of the material plane.

Type

Dimensional plane