As a long-time player of SimCity and participant in online game forums dedicated to SimCity, I have often noted that the one subject that keeps coming up, over and over again, is grids. The discussions about which grid size is best seem to have no end. Then there are the discussions about grids vs. organic layouts – and the ever popular “grids are ugly” school of thought. With the release of the Rush Hour expansion pack for SimCity4, with its focus upon urban transportation systems, discussion of this subject is likely to rise up again – as it always does.
Grids, or rectilinear forms have a long history in urban environments. Contrary to current ideas that see grid layouts as the product of modern industrial or capitalist society, rectilinear layouts have been around for thousands of years. The most obvious example in history is the ubiquitous Roman Fort – a classical layout that was always built square with a central “T” junction in the middle where the commander’s headquarters was located, which formed the center of a grid of right-angled side streets. But examples can also be found in ancient China, Japan, Greece, Egypt and colonial America.
There have also been debates about whether or not a grid street layout is ‘totalitarian’ in nature. Certainly totalitarian regimes have used structured street grid layouts as a way to symbolize their power or to effect graduations in rank of the occupants (such as in ancient Greece, China or Japan). But symmetrical grids have also been argued as being fundamentally egalitarian and democratic since it makes it easy for equitable distribution of property and street access for all. Personally, I’d consider such speculations to be irrelevant, but it just goes to show that us SimCity players are not the first people to argue about this subject.
Some will argue that the ‘traditional’ pattern of rural villages with their winding streets, twists and curves following the topology of the land are more ‘natural’ places showing more respect for the scale of ‘natural’ human living. They are probably right. Unfortunately, with the needs of our modern plumbing systems, power distribution and automotive-based transportation systems, these quaint and curvy country lanes are less efficient in handling economies of scale. In the real world, just as in SimCity, if you want to build a big modern metropolis, big scale efficiencies are needed to succeed.
No doubt about it, grids are the fastest, easiest, cheapest and simplest way to layout streets and roads for real estate development, whether it be for residential, commercial or industrial requirements. Land developers naturally favour simple grid patterns with square or rectangular building lots as these are much easier to build on or to maximize area than are irregular shaped lots, and thus, easier to sell. It is a common pattern throughout history – a swath of empty land is sold or determined to be the site of a city or settlement – then the site is drawn up with roads laid out with properties arranged for sale to individual buyers or speculators. Over time, these properties become sub-divided into individual building lots. Quasi-symmetrical grids are a natural result of this process.
When I start to build a new city, I often find myself wanting to lay my main streets exactly thirteen tiles apart to facilitate the placement of water distribution – with an underground grid running along the lines of my main streets – just like in real world urban plumbing and sewage pipes. This appears to be the easiest and most efficient way implement water distribution in the game. The best advantage of using grids is the ease of laying them down of course – but also for the ease of expansion. Small grids can be extended outwards almost endlessly, easily to allow for future developments as needed.
In our modern world with fast cars and big heavy transport trucks moving through the city, it makes sense to separate traffic uses according to speed. Thus high speed traffic is assigned to highways, mid-speed traffic is assigned to main avenues and/or boulevards and slower local traffic uses the smaller side-streets that give access to most buildings. This logical differentiation of traffic makes sense for safety and efficiency. It also lends itself well to a grid-type road layout.
Grids come in all kinds of shapes and layouts. The most obvious is that of the symmetrical grid – which often appears as a checkerboard pattern – with a series of perfect squares. This is the rarest type of grid in the real world, but an easy one to apply in SimCity. It is easy to layout ideal sized building lots, with perfectly even distribution of civic amenities (subway stations, parks, schools, etc). The principal disadvantage of this type of grid is the lack of purposeful traffic differentiations since all roads are alike. What is more common is to find a small compact grid of streets in the heart of a city (with higher density developments), with the size of the grid increasing in size as you progress outwards to reflect lower land values and lighter densities on the outer fringes of the city. This is often referred to as a stepped or scaled style of grid layout.
This leads to a ’super-block’ model of road layout where very large – usually rectangular – blocks are laid out with smaller subsidiary streets laid down inside each of these larger rectangles. These large rectangular blocks provide the principal arterial roadways for channelling commuter traffic, while the smaller side streets provide access for slower local traffic (as well as for places for kids to play road-hockey, skateboards, baby-carriages and bicycles, etc). This process of laying out ’super-blocks’ in turn leads to a hybrid idea where the smaller subsidiary streets laid inside each of the super blocks need not follow the same rigidly imposed grid pattern, but may often use an irregular grid or even perhaps organically inspired winding streets to access the interior building lots.
This brings me back to a point I made at the beginning – many people say that grids are ugly and monotonous. I agree completely. Perfectly symmetrical grids are certainly an easy way to build a functional road network in SimCity, but symmetrical grid cities all tend to look alike after a while. I don’t know about you, but I find that a bit boring and I enjoy trying to build cities with some individual character, rather than building Salt Lake City over and over again. And to be perfectly honest, I don’t find perfectly symmetrical grids to be all that efficient in distributing traffic – they are good, but not ideal.
The solution to the ‘grids are efficient but boring’ problem is to modify the grid. The super block pattern is traffic efficient, but it helps to use a ’stepped’ or scaled progression in block-sizes moving outwards from the center in combination with the hybrid pattern mentioned above – using smaller winding streets inside each block for local traffic. Most important is to use the natural topography of the terrain. Perfect grids are rare since perfectly flat land is not very common. The grid needs to be adapted to local conditions to work best, abandoning mathematical rigidity in favour of bending with a river bank.
Another solution to this same ‘grids are efficient but boring’ problem is to utilize a mixture of road layout styles. This is what is most often seen in the real world situations – with dense grid patterns found in dense urban environments while more organic or low density styles are often found in the outer suburbs or rural environments. High-speed mass transportation systems are then used to link the lower density outlaying areas with the dense urban commercial center.
Yet another realistic solution to the repetitive grid problem is to grow your city from two or more centers. Many large cities started off as two or even three smaller towns joined together. Each smaller town center should have its own style of street layout suited its own local geography. As the population grows, these towns can be joined up into one big city. This is more work and takes more care than to build one giant symmetrical grid, but it will avoid the problem having every city you build look the same, yet still retains several of the most important advantages of using grid-style road networks.
So there you have it – the story of grids! They come in all shapes and sizes, and there really is little that can be agreed upon as to which perfect sized grid works best. Grids are neither right or wrong, good or bad, merely one technique that you can use to build a traffic network in SimCity. I think that perfect grid layouts are generally fairly efficient but tend to look tedious and monotonous after you’ve seen or built a few of them. The best solution is to use a mixture of grids of differing sizes and scales, in combination with other non-grid layouts or to take advantage of natural topography to give your road layout some individual character – what I like to call an ‘irregular grid’. No two cities in the real world look alike – the same should be said about SimCity.