The Tower of Ghenjei is a gateway into the world of the Eelfinn and the Aelfinn.
It lies near the River Arinelle ten days north of Whitebridge, and it is a solid and spotless metal tower, two hundred feet high without any doors or windows. There is no opening on it; but if one draws the symbol for the game of Snakes and Foxes on the tower with a bronze knife, then a doorway will supposedly appear.
The Tower of Ghenjei is accessible through both the waking world and Tel'aran'rhiod. Once entered, the Tower Of Genjei is extremely hard to leave in the waking world. In Tel'aran'rhiod, it is all but impossible. Rand, Matrim, and Moiraine Damodred each separately ventured through twisted redstone doorframes, a pair of ter'angreal of polished redstone, to reach the realm, and have 3 questions answered. Matrim nearly lost his life, though it did change his fate.
Bayle Domon points out the tower to Rand al'Thor and Matrim Cauthon after Rand spots something glinting in the distance while traveling on the Spray down the Arinelle. Captain Domon says that the tower is a marker for river traders.
This information is collected from the Wheel of Time Wiki located at http://http://wot.wikia.com/wiki/Tower_of_Ghenjei.
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