- Published on
Mapping Speed Limits with YouthMappers and TomTom: A Fun and Refreshing Experience
- Authors
- Name
- Feye Andal
- @dfeyeandal
When we think of mapping in OpenStreetMap (OSM), we usually picture tracing buildings, drawing roads, or marking important places like schools, hospitals, and restaurants. But for our recent YouthMappers x TomTom Mapping Party, we did something a little different, and honestly, it turned out to be a refreshing change of pace!
Over two days, we hosted a mapping party with the UP Resilience Institute (UPRI) YouthMappers, bringing together enthusiastic YouthMappers members in the Philippines. YouthMappers chapters from Viscan (who even held their face-to-face session), UP Tacloban, and NEUST joined us online, making it a truly collaborative event. This session, initiated by TomTom, focused on mapping speed limits in OSM using Mapillary, KartaView, and MapRoulette, helping to improve navigation data by identifying and adding missing speed limits across key road networks.
There were 399 modified road segments with speed limits added to OpenStreetMap, thanks to the efforts of 20 dedicated participants!
This may seem like just numbers, but every speed limit mapped means a more accurate, safer, and reliable navigation experience for drivers, commuters, and anyone using OSM-based tools.
Here’s a look at what we discovered, laughed about, and learned along the way.
1️⃣ A Different Kind of Mapping Challenge
Unlike our usual and simple mapping tasks where we digitized roads, buildings, or points of interests, we were looking for numbers on traffic sign boards this time. That meant scouring street-level images from Mapillary and KartaView to find speed limit signs and add them to OSM.
For some of us, it was our first time mapping speed limits, and it felt completely different. Instead of identifying physical structures, we were on a digital scavenger hunt for speed signs, carefully checking what was missing and ensuring accuracy. And, of course, we quickly realized that speed limits aren’t always where you expect them to be.
2️⃣ What We Learned About Speed Limits in the Philippines
Major expressways don’t have a universal speed limit in the Philippines; instead, speed limits are set based on vehicle classification. Class 1 vehicles (small cars, SUVs, and motorcycles) follow one speed limit, while Class 2 and Class 3 vehicles (trucks and buses) adhere to different speed regulations as defined by transport authorities.
For this activity, we focused only on Class 1 vehicle speed limits since they are the most commonly used reference for general navigation apps. But as we mapped, we noticed a pattern in missing speed limits:
🔹 Exit ramps and gas stations – These areas rarely had posted speed limits in the images we reviewed. It makes sense—cars naturally slow down here, but having clear regulations is still useful.
🔹 U-turn slots and highway segments – Some U-turn slots are mapped as separate road segments from the main highway, which means their speed limits can differ from the highway’s. However, in many cases, speed limits for these U-turn slots are either missing or unclear, making it difficult to determine the appropriate restriction for safe navigation.
3️⃣ The Funny and Unexpected Finds
Of course, no mapping activity is complete without a few unexpected moments.
🤖 Mapillary’s AI detection isn’t perfect – While Mapillary does an amazing job detecting speed limit signs, it’s not 100% accurate. We spotted some funny misinterpretations, like food prices mistaken for speed limits. Imagine driving and seeing a “₱69.00” sign for a burger — is that the speed limit or just a really good burger deal? 🍔 😂
📸 Political campaign posters got blurred – Since we used street-level imagery, we also saw political campaign posters captured along roads. Interestingly, Mapillary blurred the faces of politicians just like it does for real people. Privacy settings at work?
These little surprises made the session even more fun and full of unexpected laughs. Who knew mapping speed limits could feel like a scavenger hunt for AI mix-ups and mystery speed limits?
4️⃣ Why This Mapping Session Was Special
Beyond the fun and laughter, this was one of those activities that reminded us why open data matters. Speed limits might not be the first thing we think about when we open OSM, but they’re an essential part of how we experience roads—affecting driver safety, traffic enforcement, and even how navigation apps calculate travel time. Without street-level imagery from Mapillary and KartaView, it would be nearly impossible to verify speed limits remotely, and even with local knowledge, missing or unposted signs make it difficult to complete the map accurately. This highlights the importance of combining crowdsourced data, open tools, and community mapping to fill in critical gaps that benefit everyone on the road.
Overall, this was a great learning experience and a chance to explore a new mapping challenge while working together as a team. It’s always fun to see how much more we can contribute to OSM, and we’re glad we got to do this with TomTom and our fellow YouthMappers.
With 399 speed limits added and 20 mappers collaborating across multiple areas, we can confidently say this was a success. Looking forward to more unique mapping adventures ahead! 🚗💨
If you’ve never mapped speed limits before, try it! You might be surprised at what you find.