This is a port of the original Wasteland mod by Silver_Weasek.
It adds a brand new worldtype with limited water and grass. Zombies can spawn in the day and it generally makes for a challenging Minecraft survival experience, especially when paired with other challenge mods.
This mod is a difficulty enhancer which simulates an apocalypse.
The ruins and other options such as bunkers can be disabled in the mod config file.
If you're looking for an even older version: Google is your friend.