For example, if you think of mentally 'cutting in half' the 4-lane two-way medium roads in a 16×16 grid, you end up with an 8×8 grid of 2-lane one-way small roads.

Getting the extra frontage makes a big difference. So if you find yourself wanting more lanes in your grid, consider using pairs of one-way 2u roads instead of going to 4u roads. Leaving a massive 14×14 unzoneable hole in the middle of the square with 2u roads is equal to the best you can do with a square of 4u roads. To emphasize how impactful that is, 50% is the same density you get from a 24×24 grid using small roads. (You can easily count this visually by considering 4×4 chunks: There are 16 total chunks in a 16×16 space, of which 8 are zonable, 1 is empty in the middle, and 7 are roads.) Then the optimal-density square grid is 16×16.īut you pay a heavy density price for the larger roads: only 50% of the area is usable for zoning. What if you're using a 4u-wide road, like the Medium and Large Roads? So you're also paying 16% less on the roads to grid the same area with more stuff.įor some concrete numbers, let's compare a 60×60 area (as it divides evenly in a bunch of ways) using a variety of block sizes and the basic small two-lane road: And for the 10×10 blocks, those 64 tiles of zoning need 40u of roads (1.6tiles/u), but with a 12×12 block you get 96 tiles of zoning out of only 48u of roads (2tiles/u). How's that? Well, you need to pay for the roads. But not only is it more dense, but it's also cheaper. Now, I admit that only about 4% more zoning doesn't sound that exciting. How much better? ⅔ of the area (66.66…%) instead of just 64%.

(Coincidentally, that's also the maximum segment length for an axis-aligned road in CSL.) So yes, it's a block length of exactly 12 that gives the best density. That shows that the 'obvious' 10×10 grid is actually only as good as a 15×15 grid: It's hard for me to grok that quotient in my head, so let's just graph it and see what happens: (Here, and in the rest of the section, we assume a small-2u-road.)įor the general case of a square of side 𝓁, the zoneable area is (𝓁-2)²-max(0, 𝓁-10)²-the area inside the road minus the area in the middle where the zoning doesn't reach-and the total area is 𝓁². For the 10×10 grid, the calculation is simple: we get 8² zonable tiles in a 10² tile area, for a density of exactly 64%.

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