Glittering Tower

The Glittering Tower is a fortified lighthouse south of the Elven city of Lothern.

Approaching Lothern, the first thing a mariner sees is the Glittering Tower -- a great lighthouse filled with thousands of lamps, situated on a rocky isle in the mouth of the treacherous straits of Lothern. This titanic fortress guards the approach to the Emerald Gate, the first sea-gate of Lothern. Anyone approaching the Emerald Gate can easily be caught in a crossfire between the massive war engines in the Glittering Tower and those on the Gate itself. The sight of these imposing bastions is enough to turn all but the most insane attackers away.

Source

 * Warhammer Armies: High Elves (8th Edition) pg. 9.