Kind of like what Swat said.
It was just a giant, organised roleplay that became a hub for some of Blockland's more hardcore roleplayers. However, as time went on, I had less time to run the server and it started going downhill. It could have kept going a bit longer, I think, but it wouldn't have ended very well. I figured we may as well close while the server was ahead, or at least before things got much more worse.
The actual server, however, was just a giant, open roleplay set during a zombie-apocalypse.