The OSM Urban Road classification guidelines for India dictate a number of high-level directions on mapping roads in Indian cities. When Devdatta and I tried to fix some classifications in Pune, we realised that the current guidelines don’t provide a solid base for decision making, in an “if X, then Y” way. So we decided to observe, annotate, experiment and retrospect on whether a classification makes sense.

We realised that to map a road, one must understand how a road is perceived, and its purpose in the larger scope of the neighbourhood, locality or city. This gives the road a purpose, and that purpose defines its classification. The purpose or intent of the road is not enough to classify it, so we tried to observe a few other factors that characterise roads in major Indian cities. Here’s what we found.

1. Much like a river, a road begins somewhere and merges into another road. As roads connect with each other, the larger road essentially “collects” traffic from a smaller road. However, it is not necessary that a smaller road feeds into a larger road. Often, it might feed into a road of the same size, but with elevated purpose.
2. Some roads serve the same purpose but could vary wildly in their characteristics, including the width of a single lane.
3. Many collector roads can be easily identified using tell-tale signs such as the presence of speed bumps, traffic signals and dividers.

The observations led us to try and categorise roads based on a few factors:

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