Uthtower - Locations

There is an actual tower with the name Uthtower and a kingdom from long ago that had the same name, with the tower as its center of power.

The kingdom was located between Waterdeep and Neverwinter founded by Uth Myrmoran of Tavaray.
It began with the building of the tower in 146 DR on a tall hill on the coast by Uth and his Shoon mercenaries.
A powerful archmage named Iniarv served as the royal mage.
The kingdom was an ally with Neverwinter against the orc horde invasions alongside the kingdom of Phalorm and the dragon Palarandusk.
In the war against the orc hordes of 615 DR, a great battle was taking place in the lands between the Uthtower and the inland fortress called Iniarv's Tower.
King Uth VII awakened Iniarv who had survived the ages as a lich, begging his aid.
The lich, coldly cruel and wrathful of being awakened to this world, performed high magics to cause the ocean to rise up and swallow the entire kingdom - drowning orc, man, and all other life alike - forming the Mere of Dead Men out of the entire now-destroyed kingdom (and the ongoing magics cursing the High Road to never escape the reach of the swamp).
The Uthtower itself sunk partially into this swamp, forming a sort of catacombs that the black dragon Chardansearavitriol (called "Ebondeath") took as a lair in 685 DR, becoming the undisputed ruler of the swamp for centuries.
One of the most well-known successes of the Cult of the Dragon, Ebondeath was transformed into a Unknown in 922 DR.
The ritual consecrated the Uthtower as sacred to the Church of Myrkul (also creating Ularan Mortus among the sacrifices).
In 1202 DR Ebondeath vanished - the priests of Myrkul believed he had become a god and came to the Uthtower as a pilgrimage of devotion.
In 1358 DR the Uthtower was completely swallowed up beneath the swamp.
With the appearance of the Eye of Myrkul in the sky in 1372, the tower rose from the murk and a great legion of the dead attacked nearby lands - but was unfocused by any leadership, and it sunk again soon after.
Recently, in 1489 DR the tower once more rose, leading to the attack on Leilon and has been thought to be similarly short-lived as the Eye of Myrkul left the sky - however, it is merely hidden behind the tail of the Dragontail Comet, and the tower remains.

(Important other information in the links to Mere of Dead Men and Church of Myrkul and Ularan Mortus and Ebondeath )