My Minecraft Adventure Map Won't Show Up In Singleplayer Saves?

I downloaded the Adventure Map: Under The Dome and have been able to successfully install the resource pack to the point where I can select it from the in-game screen. However, the map itself is not showing up in the in-game world select screen. Does anyone have any ideas as what to do?

Added (1). The map is up to date with 1.8.8.

Try looking in the map's folder because sometimes mapmakers put there map in another folder w/ instructions on how to install it.