Eberron - Echoes of Prophecy
The city now known as Sharn was built upon a foundation that dates back thousands of years before humans ever settled Khorvaire. During that time, the hobgoblin Dhakaani Empire’s greatest city was carved into the jagged cliffs that Sharn now towers over. This city was called Ja’Shaarat. This metropolis didn’t rise toward the skies, like Sharn does. Instead, the architects of the Dhakaani built a vast number of chambers and tunnels into and under the ground. As the city grew in size, the Dhakaani eventually would build great monolithic buildings on the plateaus above the Dagger River that would later serve as the foundations for Sharn. When the Daelkyr invaded Eberron, the city was devastated, and the hobgoblins never had a chance to restore it to its greater glory.
Thousands of years later when human settlers from Sarlona began to explore Khorvaire, the Dagger River was stumbled upon. The river led Malleon the Reaver and his explorers to the site where Ja’Shaarat once stood. There he enslaved what goblins still resided in the ruins and erected a fortress within the ruins. He sealed off the lower wards of the ancient hobgoblin city and named the city Shaarat, as a result of stories told by the goblins he enslaved. For 600 years, Shaarat prospered and grew into a powerful metropolis once again. Breggor Firstking, the first ruler of what would become Breland, eventually conquered Shaarat and renamed it Sharn.
The last remnants of the city of Ja’Shaarat were buried by the vast earthquakes set off by Halas Tarkanan who nearly leveled all of Sharn during the War of the Mark. Expeditions to the lower levels known as the Cogs occasionally turn up the odd relic but no one was succeeded in discovering a way down into the lost treasures of the old capital of the Dahakaani empire.