Harnaidan, a major city on Muunilinst, was the planet's capital and the central hub for the InterGalactic Banking Clan. A skyhook connected its towering structures to the orbital station known as High Port. In 21.66 BBY, during the Clone Wars, Republic forces attacked Harnaidan.
Situated on the Outer Rim planet of Muunilinst, Harnaidan, a prominent and substantial city of the Muun, functioned as both the planetary capital and the operational center for the InterGalactic Banking Clan. The urban landscape was characterized by towering spires, some exceeding four kilometers in height. These spires, deeply rooted in the planet's bedrock, served as the foundation for a skyhook that provided a direct link between Harnaidan and High Port Space Center in orbit. These immense constructions were exclusively controlled by the Banking Clan.
Underneath Harnaidan's surface existed a network of subterranean lakes warmed by magma vents at great depths. The city's ordinary citizens ventured into these waters to gather mollusks and algae. The city was surrounded by volcanic formations. The metropolis itself showcased shining marble buildings designed in the Neo-Classical style and accommodated over fifty million Muuns. The city's design was well-organized, contrasting with the chaotic urban environments of places like Denon and Coruscant.
During the Clone Wars, which pitted the Galactic Republic against the Confederacy of Independent Systems, a CIS Shadowfeed report originating from Harnaidan pointed out that the InterGalactic Banking Clan's ability to function within Republic financial systems, due to their required non-exclusivity, had increased the value of the CIS credit. According to a monthly statement from Bank Communications Officer Lo Vapeet, included in the report, the CIS credit was valued at more than half the value of the Republic credit in numerous Mid Rim markets and served as the sole currency for hundreds of Outer Rim worlds.
In 22 BBY, during the Battle of Muunilinst, Obi-Wan Kenobi, a Jedi General, led the Grand Army of the Republic in an assault on Harnaidan. Before engaging the Separatist Droid Army outside the city, Kenobi deployed The Muunilinst 10 in their gunship to infiltrate the city. Although their gunship was destroyed, the elite squad successfully fought their way through the streets to the massive defense cannon defending Harnaidan and destroyed it.
With the cannon disabled, the Republic extensively bombarded Harnaidan using Self-Propelled Heavy Artillery, reducing entire city blocks to debris. To counter the enemy's advance, IG lancer combat droids under the command of Durge, a Gen'Dai mercenary, engaged the Republic forces, destroying many All Terrain Tactical Enforcer walkers and heavy artillery units. Clone lancer troopers led by Kenobi were deployed to halt Durge's forces, with Kenobi seemingly defeating Durge in a duel. The Jedi then met up with the Muunilinst 10 and captured the Separatist command center, though not before a regenerated Durge attacked the clones; however, the mercenary was once again defeated when Kenobi used the Force from inside Durge's body, causing him to explode.
The forces within the city were soon surprised by the arrival of Anakin Skywalker in his starfighter, pursuing Asajj Ventress in hers. Skywalker's attempts to shoot down Ventress resulted in damage to several of the city's buildings. Shortly after, Republic Acclamator-class assault ships landed in the city and were filled with Muun and Neimoidian prisoners captured from the devastated city.
Harnaidan made its debut in "Chapter 2" of the Star Wars: Clone Wars animated microseries, broadcast on Cartoon Network on November 10, 2003. Art Director Paul Rudish developed the city's overall aesthetic as a banking center, drawing inspiration from the design of the United States dollar bill, including its architecture and green color palette.