Barcelona gezien vanaf de heuvel Tibidabo © E. Kieckens
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Cool Walks is an app that has been designed to show users different walking routes that they can take to their intended destinations. Users can choose the most direct route, a route in the shade that may take a little longer, or they can set the app to “vampire mode,” avoiding direct sunlight at all costs. Users can also use the app to find water fountains, or places to shelter from the sun.

Example of a route in Barceloneta on Cool Walks

The app uses Lidar to create high-resolution models of the different heights of the ground, accurate to within 10 centimeters. Lidar stands for Light Detection and Ranging and is a detection method that uses light in the form of a laser pulse to measure variable distances to the earth. These light pulses – in combination with other data recorded by the airborne system – generate accurate, three-dimensional information about the shape of the ground and the characteristics of the ground surface.

3 different algorithms

This information is then combined with data about the sun’s path to calculate where shade is located at any given time of day.

“We wanted to generate different options so you could pick faster or cooler routes and we calculated three different algorithms,” Marc Montlleo, director of environmental projects at the city planning department (Barcelona Regional) told The Guardian newspaper. “It’s nice for a public agency to work with data that the city gave to us, to demonstrate that it’s feasible to come up with technological solutions to climate change.”


Although the app maps only one neighborhood of Barcelona, known as Barceloneta, it is hoped that the research will yield information on how the city can adapt to extreme heat to protect its citizens and economy.

Also read about how Lidar systems are essential in the development of autonomous driving cars.