What is GreenRah?

GreenRah is a walking map for Lisbon that helps you choose a route that feels better, not only one that is faster.

In hot, hilly cities, the shortest route is not always the most comfortable. GreenRah lets you enter a starting point and destination, then compare route options based on what matters for your walk.

GreenRah combines six layers and environmental data to understand conditions along the streets: local weather, temperature and sun exposure, time of day, shade from surrounding buildings, elevation and slope, walkable streets, to calculate the final Thermal Comfort Score. Together, these layers help us look beyond distance alone and identify routes that may be cooler, less exposed, or easier to walk.

Alongside the usual Fastest route, GreenRah can show:

• Heat Smart routes, which lean towards shade, lower heat exposure, and more comfortable streets when the available data supports it.
• Accessible routes, which aim to reduce steep slopes and avoid stairs where this information is known.
• Route comparisons, so you can see the trade-off between time, distance, heat exposure, shade, and elevation before choosing your way.

For example, the fastest route may save a few minutes but involve a steep hill in direct afternoon sun. A Heat Smart or Accessible alternative may take slightly longer while offering more shade, a gentler climb, or a more comfortable walking experience.

GreenRah is designed for real life: commuting, visiting a city, walking with children, running errands, or simply avoiding the harshest streets on a hot day. We focus on Lisbon today, and then we will cover the whole of Portugal. Our vision is Europe.

GreenRah is operated by GreenRah OÜ, based in Estonia.

Our tagline is: The cooler way.