Data Tunnels are found in Carthage, linking the central dome to the four surface sectors (Desert Sector, Forest Sector, Ice Sector, and Mountain Sector). They appear as blue streams of data and energy, similar in appearance to the interior walls of a tower.
The tunnels connect to the other sectors via openings in the Celestial Dome. Jeremie can temporarily disable the tunnels to allow the Lyoko Warriors to leave Carthage via their vehicles or the Skidbladnir. This was first seen in "Exploration".