To encourage people to use the train to go and explore nearby cities, railway service Thalys creates three interactive billboards. Each billboard represents a city, and each is host to more than 1,000 unique sounds from that city.
Pedestrians who walk past these billboards are invited to plug in with their personal headphones and start exploring. So instead of using headphones to block out the city, they are made to use them to rediscover one.
When a billboard becomes a listening device
The mechanism is the whole point. A city map on a billboard doubles as an audio interface. Plug your headphones into different points and you unlock different sounds, turning a familiar out-of-home billboard format into a self-guided micro journey.
That matters because the interface makes exploration feel self-directed, which is why the destination becomes memorable before the trip starts.
In European high-speed rail travel, nearby cities compete on spontaneity and sensation as much as price or schedule.
Why it lands
This works because it flips a modern habit. Headphones usually remove you from your surroundings. Here they pull you into a destination you have not reached yet, using curiosity and discovery instead of discounts and slogans.
Extractable takeaway: If your audience already carries an interface, design the experience so their default behavior becomes your entry point. Then reward exploration with variety, so people keep trying “one more” interaction.
What Thalys is really selling
The real question is not how loudly you advertise a nearby city, but how quickly you make it feel explorable.
For travel brands, a sensory preview like this is stronger than another fare-led message.
The campaign sells proximity. You do not need a long promise about travel. You get a sensory preview that makes the next city feel close and personally explorable, even in the middle of your current one.
What travel marketers can lift from this
- Turn passive media into a tool. If the unit does something, people approach it voluntarily.
- Build a library, not a single message. 1,000+ sound fragments makes repeat interaction feel natural.
- Use “rediscovery” as the hook. Familiar objects can become new experiences with one clever twist.
- Let the audience choose the path. Interactivity creates viewer control and longer dwell time.
A few fast answers before you act
What is Thalys “Sounds of the City”?
It is a set of interactive billboards that let passersby plug in headphones and explore a city through a large library of location-specific sounds.
Why use sound instead of visuals?
Sound creates immersion fast and feels personal through headphones. It also differentiates travel advertising that usually relies on images.
What behavior does the idea exploit?
People already carry headphones and use them in public. The billboard redirects that habit from blocking out the world to exploring a destination.
What is the main metric to watch for OOH interactivity like this?
Dwell time, repeat interactions per person, and any measurable lift in intent or searches for the featured routes and cities.
How can another brand apply the pattern?
Identify a “portable interface” your audience already has, then design a physical touchpoint that turns exploration into the reward.