Alne

«Aarun» is the largest city at the base of the World Tree in ALfheim Online. It is known to be a neutral city. It is also called as Yggdrasil city. It serves as the headquarters for some clearing guilds, and also holds Kirito's previous home before reclaiming his and Asuna's home on the 22nd floor of Aincrad.

The city, Aarun, also holds four dungeons located north, south, east and west of the city, and at the end of these dungeons is a way leading to Jotunheim. There is also a secret alley that is not shown in the map that leads to a locked wooden door that can only be opened with a certain key obtained after escaping Jotunheim through the said door. The door leads to a staircase leading to Jotunheim.

Near the foot of the World Tree, stands a gate that leads to the dungeon that leads to the top of the World Tree, players must defeat the guardians guarding the inner gate to be able to pass through and complete the first Grand Quest that would be to meet the Fairy King Oberon and grant the successful fairy race with eternal flight.