Side effect: Hexagonal layouts can get you out of a jam Folco Quilici/Alinari Archives via Getty Images

Life is sweet in the honeycomb. City planning has long depended on rectangular networks – they’re simple and, urban planners say, reduce congestion. But it turns out that connecting streets to form hexagons instead of rectangles might lead to less traffic.

In a study, Luis Eduardo Olmos and José Daniel Muñoz at the National University of Colombia find that designing cities so only three streets meet at any given intersection – as they do when they form a honeycomb shape – could help get rid of traffic jams.

The team ran a simple mathematical model allowing cars to drive diagonally in one direction, as might happen during rush hour when commuters all head home at once. For a square street network such as Manhattan, for example, the imaginary cars would run east and north to leave the city.


With only a few cars, traffic flows smoothly, and when too many vehicles appear, traffic clogs. But in between those extremes, there’s an extended intermediate state, where small traffic jams clog traffic in bursts across the network.

When Olmos and Muñoz applied their model to honeycombed streets, however, they found something quite different. As the number of cars increased, the traffic transitioned suddenly, like water turning from liquid to solid: free-flowing traffic became a jam.

Crowd-pleaser

With the addition of a few traffic lights to break up the flow, Olmos and Muñoz found that cars driving along honeycombed streets kept moving at densities that had already caused the rectangular network to clog up.

The model is a first approximation ­– it doesn’t include pedestrians, landscapes or buildings, for example – so the authors plan to create a more-detailed simulation.

But as Eran Ben-Joseph at Massachusetts Institute of Technology quipped in a 2000 review of hexagonal city planning, “How would strangers navigate the streets of Hexagonopolis?” Even in the face of the new study, hexagonal cities remain “a concept that may work in theory but not in practice”, he says.

However, even if the honeycomb model doesn’t work in real cities, the same concept could be applied in other situations, the authors suggest, such as information packages travelling through the internet.

Journal reference: arXiv.org, DOI: arXiv:1610.07438v1