- "There are loads of infected in the old railroad facilities. In this abandoned reload depot, in the darkness of sewer connected through the drain holes, they established a nest and started to evolve. Who knows what kind of sick mutations will develop, if this place will not be cleansed in time? These hanging containers look like they could be useful to close the drain holes."
- —Loading screen
"Holy Year Tunnel" is a quarantine zone challenge available in Dying Light's downloadable content pack "Cuisine & Cargo". It is located in the Slums. The entrance is immediately northwest-north of Rais' Headquarters, which is accessed during the quest Pact with Rais.
You are to wipe out all the infected within the zone, but also drop two cargo containers on top of two manholes, where virals endlessly spawn from. To drop the containers, you have to jump to each container (Be aware that virals can also perform this jump) and hit a control panel above each container to release it and drop it down over the manhole. Once the containers are covering the manholes, clean out any remaining virals and biters to successfully complete the quarantine zone objective. There are two GRE chests in the north-west part of the zone's main area, and an aditional 3 stored within a container behind a locked door near the second manhole.
- There is also a silver chest located in the back-most cargo container on the second-from-left train track. However, while it is possible to interact with it at first, upon doing so produces no result, and the chest cannot be interacted with again. As of current, there is no known way to open this silver chest.