DecaMillenia (Pop: 11,275,225) in SimCity 2000

This world record city of 11.27 million sims was built primarily using the SimCity Urban Renewal kit. The basic design strategy revolved around compressing the 3x3 residential zones so that more could be fit into the 128x128 city grid. The thing to remember here is that each 3x3 zone doesn't need all 9 tiles to sustain its population. It only needs one. The ones it doesn't need can be erased and built over. And it works... delivering virtually the highest possible population under the 140 arcology limit.

The Procedure

First, 140 arcologies were built on the flat, bare land and allowed to reach their highest populations. Each arcology was then magically erased using the magic eraser. The arcologies' populations remained, but the space they previously occupied was available for additional zones. Then SCURK was loaded, and a strip of 3x3 residential zones was laid down to occupy the 128x3 area on one side of the map.

Next, the city was saved, and SimCity 2000 was loaded. The magic eraser was then used to erase 6 of the nine tiles each 3x3 zone occupied, meaning that an entire 126x2 strip had to be erased for each strip of 3x3 residential zones (see the following picture):

Once these tiles were erased, the SimCity Urban Renewal Kit was once again loaded, and another strip of 3x3 residential zones was laid down, occupying the erased tiles of the previous strip of 3x3 zones.

No pain, no gain

This was repeated about 126 times, meaning that both SCURK and SimCity 2000 had to be loaded 126 times- that's 252 times each was loaded by the time the city was finished! The work load was not nearly as bad as you might think, because A) I used a batch file to alternately load each program upon quitting each one, and B) I spread the whole process over about 10 days, meaning that I only had to do about 12 strips per day. Yes, it took a lot of patience, but it was tolerable. The end result: a 3:1 compression ratio of 3x3 residential zones. I was able to fit 3 times as many buildings in the same amount of space than ordinarily possible.

Getting greedy

But I didn't stop there. Using the magic eraser once again, I erased a 2x2 strip running perpendicular to the 3x3 strips, and filled in this space with high-density 2x2 zones. Each 2x2 strip was 1-tile length away from the other; the 1x128 strip in the middle of each 2x2 strip was occupied by the 3x3 zones. In addition, the outside of the map, where 2x2 and 3x3 aren't allowed to be built, was filled in with 1x1 industrial zones.

There is one major disadvantage here. The city will decay very quickly when allowed to run (taken off pause). This is because there are no roads or support zones to keep the population happy. Another side-effect is that different buildings will show up when the city is rotated. In one view, only the 2x2 condos will be visible, while another view will show only the 3x3 condos.