The towers are where XANA launches its attacks. The only way to stop XANA's attack is to find the infected tower and have Aelita deactivate it by entering the Code "Lyoko" on the console inside.
On the edge of each region is a "Passage Tower" (one per region).
OUr heroes enter the Passage Tower. They move onto the platform in the center of the tower and wait. There, they drop into empty space (a vertical cylinder with digital displays moving up and down) until they cross a sort of "airlock" indicated by perpendicular digital displays. The heroes then arrive on the circular platform of another Passage Tower ; when they exit, they are in another territory.
About the other towers :
Lyoko's Towers are data warehouses wich constantly search Lyoko's network to find information.
The towers' data warehouses are connected across the four regions of Lyoko by a network of underground cables.
All these towers are connected to XANA's and the supercomputer by the digital cables. All these towers are numbered, but we don't know the total number.
These digital cables are the path that XANA takes to inject the virus in a tower. Towers being connected with the ground cable network, they are thus doors access to the Earth for XANA.
