Mudan was once the site of a Dwemer settlement, but it was later abandoned, much like other settlements. The Mudan Ruins were more on the surface than they were sometime later. During the Interregnum, around 2E 583, the Mudan Ruins were explored by the former grandmaster of the Morag Tong, Rythe Verano, on his quest for the Simulacrum Rubric. Verano was intercepted by Naryu Virian and her cohort, Boldehk, a powerful Warden. Their conflict was interrupted by a swarm of Dwarven Animunculi, later involving a Dwarven Colossus. Verano did not survive the Colossus' attack, but both Virian and Boldehk left unscathed, as Naryu began her hunt against the Seven Secretives.
Many years later, during the Blight outbreak in 3E 427, the Mudan Ruins were flooded and became colloquially known as the Mudan Grotto. The local water fauna largely inhabited it. An adventurer had attempted to loot the Mudan Grotto but had died in vain. Deep in the ruins were more Dwarven Animunculi and the artifact known as the Dragonbone Mail, a rare cuirass blessed by the Imperial Battlemage, Zurin Arctus.
A Dwarven Colossus at the ruins ca. 2E 582