Akhlaur's Tower

Akhlaur's tower was the created by the eponymous wizard in 12th-century DR.

The tower resides in the middle of the swamp that bear's the spellcaster's name and has long since been abandoned since he called it home. As the waters of the swamp grew, the tower sunk, and became partially submerged. In the Year of Wild Magic the tower stood out enough to still be entered and explored.

Considering how powerful a wizard Akhlaur was, there were likely a wealth of magical items and arcane secrets inside.