Olann Island is a
Apparently made in 10 days, Olann Island is an attraction resort with a things like a golf course and huge casino. Best of all there is a massive working roller-coaster and water flume. You can place a mine cart on the roller-coaster and ride it, and climb the stairs to the top of the flume and float down to a waterfall.
To play, simply unzip the folder and move it into your Minecraft Saves folder. It will then be available to play next time you open Minecraft.