End portal

 are naturally occuring structures that are used to travel into The End. It can only be found in strongholds, and it consists of a horizontal frame of 12 Ender Portal Frame blocks, organised into a roughly square shape, five blocks wide, five blocks long. Upon placing an Eye of Ender in every Ender Portal Frame block of a specific portal, the portal activates, creating 9 Ender Portal blocks inside the frame, and allowing the player to access The End. The is part of the 1.9 pre-release 3 update, but was unfunctional until pre-release 4. The official release for the Portal is to be 1.9.

s are found horizontally within the portal room of a stronghold, over a pool of lava with a staircase leading up to the portal and a Silverfish spawner. Some of the portal frame blocks already have Eyes of Ender in them (usually 1-2), while the rest do not.

 * Note that the placement of cracked blocks in the incomplete portal varies on the seed

Behaviour
Stepping into an activated Ender Portal immediately opens up a loading screen, and transports the player to The End, leaving no time to back out, unlike the Nether Portal. Upon entering The End, a five by five horizontal platform of obsidian is spawned at (0,72,0), often in midair, and the player is placed on top of it. Due to the lack of a return portal being generated, the Ender Portal is one way and the End cannot be escaped from without dying.

The black portal blocks emit light of level 15, which as powerful as Glowstone and is the brightest light level there is. It only takes one block of portal to teleport to The End. Through the use of an inventory hack, you can place these portal blocks anywhere, and they will still function as if they were a complete portal. The only exception to this is in The End, where the portal blocks will decay instantly.

Trivia

 * End portals are very thin, and only the top face is solid. You can jump through the bottom face, and not the top face.
 * End portals emit light, like Nether Portals.
 * The portal does not deactivate if you somehow manage to destroy the frame.