The Adrian Union is a SimCity union which was formed in October 2006 as a sub union of the USCN by the three CJs of Georgiapolis, Genava and Manteria. In October 2007, one year after the unions initialization, it took its current form as a standalone SimCity union after long-term turmoil between the Adrian members of the USCN and the others.

During its time in the USCN, the Adria (the continent on which AU operated) was known as the most exclusive and established continent because of its high quality cities and community events such as the Adriovision Song Contest. The contest was a way for all the nations to gather in a unique environment, something that other continents did not offer.

Although the Adrian Union has historically been a European styled city journal union, other styles are accepted as long as the city building is of a high quality.

Any nation is allowed to be on the map even if it isn't approved for membership yet. This is a way for everyone to take part in the Adrian Union experience, even if they are not exceptional city builders.

The unique was of communicating in the USCN is not through CJ storylines but through News articles which can be posted on the news forum. These articles are able to set diplomacy status as well as a means to maliciously spread propaganda if your nation so desires.