Kamui's Dimension

The Other Dimension is an alternate space which can only be accessed through Space–Time Ninjutsu. It is unknown all of space-time ninjutsu are connected but Kakashi's Kamui and Tobi's Space-Time Migration have the same other dimension. Kakashi used this as an advantage in the battle between them.

Shown when Tobi warped Sasuke Uchiha and Karin there after the battle at the Five Kage Summit, it was shown to have a great deal of randomly composed and sized rectangular prisms.