“Why Am I Hiking on a Road?” and Other Routing Mysteries Solved
August 2, 2023
There’s no doubt that komoot makes it easy to plan the best adventures for you, but even we have to admit that its route choices are sometimes…surprising. You may have found yourself on an unexpected route in the past, asking yourself things like, why did komoot send me on a gravel road when I selected road cycling? Why does my route bypass an official trail if there’s one nearby? Why am I still being routed along a road when I’m trying to have a relaxed family ride?
Usually things happen for a reason, so this writer put on her detective’s cap and sat down with komoot’s routing team to understand how the routing actually works (and how to use that information to plan even better adventures).
So, why did komoot send that road cyclist on a gravel path?
There could be many reasons. The available road could’ve been a heavily trafficked road with a high speed limit. It could’ve been a perfectly good road that was just labeled incorrectly in Open Street Map (OSM - we’ll explain in more detail later). Or it could’ve been a smooth, asphalt dream, but included a gradient of 20% or added 100 kilometers to the route’s distance.
How does komoot know that a cyclist doesn’t want to ride an extra 100 k on dreamy asphalt?
It doesn’t. But the algorithm needs to choose a route between A and B, and bases this route choice on the information available. It weighs up the options and attempts to choose the right route for the given circumstances.
What circumstances are those?
The information you give komoot — your sport type plus the feedback we gather as we test different versions of the routing algorithm. For example, when we route you up 20% gradients on road cycling routes, the community tends to let us know that that’s not a fun ride, so we build that information into the algorithm.
Makes sense. I tried riding up a 12% gradient recently, and that was hard enough. But I definitely know riders who’d take the distance over the shortcut…
The algorithm’s default is to choose the shortest, most pleasant route between A and B as we’re trying to make it easier for anyone to have an adventure. For the folks who prefer more of a challenge, it’s simple to tailor the route by using way points to extend the distance or Highlights to include particular places on your route.
So, is it also true that the hiker got routed away from the official route because the “non-official” route was a shorter distance between A and B?
It might have been shorter, yes. Or it may have sacrificed a segment on an official route you know, and replaced it with a segment from another official route. It’s also possible that the OSM labels conflict with what you see on the map. Say, what looks like a short gravel stretch on the map is actually labeled as a private road by the OSM volunteers. So to keep the route shorter, and away from the private road, it skips the official route.
Private road you say…
“Private Road” is one of the OSM labels. The difficulty is that the definition is vague; it could be private property — if you walk on it a farmer will rush out with a rifle — or it could just be a road where the council’s refuse removal doesn’t operate. The available OSM data doesn’t always provide that level of detail. Ditto for so-called “barriers” on the map, which could indicate a few bollards to prevent motor traffic, or it could be a six-foot perimeter boundary that’s completely impassable.
By the way, can you clarify OSM, since you’ve mentioned it five times so far?
Open Street Map. This is the open-source map data we use for komoot maps. It relies on a community of volunteers to keep it updated, and generally they do a great job. But as you’ve probably noticed, it’s not a flawless system. It’s not unheard of for a hiking trail to be assigned the wrong SAC (Swiss Alpine Club) grading, or for one volunteer to label the surface type as “packed gravel”, when most people would describe it as “rocky.” This is where tailoring your route becomes important, and features like Trail View are really handy here as you can cross-check photos of the route against your own expectations.
Right. So this routing business sounds like a bit of a balancing act, weighing up all the data available about a route and matching that to what we know about the community’s preferences.
Exactly. Every time komoot plots a route for you, it takes into account all the OSM and elevation data available, and assigns a meter-by-meter score against metrics like surface type and trail grading. Each metric is given a different weighting, depending on things like your selected sport. For example, if you’re after a gentle family bike Tour, the surface type is given less weighting as you aren’t as reliant on smooth asphalt in the same way a road cyclist is. The great balancing act is also why the algorithm sometimes makes “strange” choices.
By “strange choices,” do you mean sending the family of bike tourers down a busy road instead of the quiet gravel track?
Maybe… Remember how we mentioned the vague definitions of OSM labels earlier? It could be the case that the gravel track included a “barrier” label. In the three-dimensional world, it’s very obvious that the “barrier” is a small gate that can be easily opened and closed behind you. However, in the two-dimensional map world, we don’t know if it’s a little gate, or that impassable six-foot wall, so we take the safe option and route you along the road instead.
Interesting. I think it’s starting to make sense. So, is there any way that we can counteract these strange routing choices?
Yes. The most important thing to remember is that the routing algorithm is not a person and there are nuances in the data that are impossible for it to pick up on. We’re constantly improving the algorithm but we also have a bunch of features that bring the map to life. To get the best route (one which aligns with your skills, experience, and goals for your adventure), use komoot’s route as a starting point and pay attention to the map. Use Trail View and Highlights on or near the route to help paint a more accurate picture of your adventure-to-be. You can also use different map layers, such as Satellite View, to get a better idea of the landscape. And, of course, if a route warning pops up, pay attention to it!
The main takeaway is this: All routes are better when you add a little “human” touch, so do spend an extra few minutes looking at your route and making it your own.
Thanks for the insights!
You can test out their tips and see their handiwork by planning a route now. Or you can get more specific tips for route planning on the Adventure Hub: