+300%
Heat deaths surge
Fatalities spike in heatwaves. By 2050, Lisbon faces 50 days above 35°C. Urban heat islands add 5–10°C.
The best path isn't
the fastest.
It's the coolest.
GreenRah: The cooler way. Six live layers pick the street that stays in shade, built for Lisbon's hills, heat, and midday sun.
- Walkers
- Tourists
- Seniors
- City teams
GreenRah2:47 PM · 36°C
Heat-smart routeComfort 98
FROMRua da Imprensa à Estrela
TOCiclovia da Rua da Prata
Lisbon · Heat-smart path
CoolestFastest
Coolest
18 min
Fastest
14 min
The crisis
Heat kills.
Maps don't see it.
Portugal ranks 6th in Europe for heat deaths. Every summer, Lisbon sends people down the sunniest street at the worst hour.
Heat-blind
Navigation ignores heat
Google Maps, Apple Maps, and Waze optimise for speed, full sun at midday, steep hills, no thermal awareness.
105K+
People maps miss
105,000 seniors, 60,000 with disabilities, 20,000 parents with strollers, 6.5M tourists, walking unprotected.
How it works
Six layers.
One score per street.
Weather, sun angle, building shadows, slope, and the walkable network roll into a Thermal Comfort Score, then GreenRah routes you on the walk your body can take.
Live weather
Temp · humidity · wind · UV
Solar position
Angle · radiation · time
3D shadow map
Buildings · shade footprint
Elevation & slope
Grade · effort · access
Walkable network
Paths · crossings · streets
Thermal Comfort Engine
All signals → one score
How we score every street.
Shade, heat, slope, and effort are weighted for the hour you're walking, not a generic fastest line. The result is a route you can actually take at 14:00 in August.
See coolest vs fastest before you go
Shade %, heat, and hills side by side, no surprises once you leave the door.
GreenRah's routing draws on peer-reviewed research: Transportation Research Interdisciplinary Perspectives found 12% more shade for just 2% extra travel; IOP Conf. Series showed shade-routes cut walking cost 11–35%; and Int'l Journal of Biometeorology confirmed UTCI predicts perceived heat (r=0.81).
Live shade
Comfort moves.
So should your path.
Sun and shade shift through Lisbon every hour. GreenRah reads that motion and keeps your walk in the cooler band as the city heats up.
- Find reliefShaded streets, covered waits, cooler pauses.
- Walk with confidenceShade, slope, and access balanced for every body.
- Plan better citiesShow teams where cooling saves the most walks.
Why GreenRah
Shade maps don't route you.
We do.
Fastest-path apps ignore heat. Shade viewers stop at the picture. GreenRah fuses both, plus slope, for hot, hilly Lisbon.
ToolHeatNavSlopePortugalAccessible
Google Maps○
ALKOO
ShadeMap
Komoot
Citymapper○
GreenRah
Google Maps
HeatNavSlopePortugalAccessible
ALKOO
HeatNavSlopePortugalAccessible
ShadeMap
HeatNavSlopePortugalAccessible
Komoot
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Citymapper
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GreenRah
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A shade picture is not a route. GreenRah tells you which street to take, this hour, this heat, these hills.
Roadmap
Built for Lisbon.
Scaling to Europe.
Stage 1 · Now
MVP & Pilot
Web app live. Early users in Lisbon stress-test the cooler-path experience.
In progressStage 2 · Growth
Seniors & Premium
Heat-vulnerable walkers, UV guidance, community partnerships.
Coming soonStage 3 · Scale
City Platform
Insight dashboard for planners. Europe is the vision.
EuropeWho it helps
Bodies that feel heat first.
Routes that respect that.
Less sun and less strain on the walks where 35°C is more than uncomfortable, it's a risk.
Seniors
More shade on days when midday streets are a medical risk.
Mobility & families
Not sent up the hottest hill with a stroller or limited mobility.
Tourists
6.5M visitors, know which alley stays cool at 14:00.
Cities
See where shade is missing. Aligned with UN SDGs 3, 9, 13.
FAQ
Questions
before you walk.
01 What is GreenRah?
A pedestrian routing app for hot cities, starting in Lisbon. Heat Smart shaded walks and gentler Accessible paths. Tagline: The cooler way.
02 What is the Thermal Comfort Engine?
The sixth layer. Weather, solar position, 3D shadows, elevation, and the walkable network fuse into one score per street, your route.
03 How is GreenRah different from Google Maps?
Google Maps optimises for speed. Shade maps don't route you. GreenRah does heat-aware turn-by-turn with slope and accessibility, built for Lisbon.
04 Is this based on real science?
Yes. MIT: shaded route 1.3% longer, 8.8% less sun. CoolWalks 2024 and Dean Neto's Lisbon research underpin the model.
05 Who is GreenRah for?
Tourists, seniors, families, people with limited mobility, city teams, and partners who want heat data to protect walkers.
06 Is there an iPhone or Android app?
The web map is live at greenrah.com/app. Native apps are coming, request early access in the form.
07 How can a city or investor work with GreenRah?
GreenRah OÜ, Tallinn, Estonia. Lisbon first, Europe next. Use the contact form for investment, municipal, press, or partnership enquiries.
08 Where does GreenRah work?
Full routing and shade coverage across the EU and Great Britain today. Other continents are rolling out over the next few months, city by city.
Contact
Send a message.
Investment, city, press, or early access, we reply within a few days.
Get in touch
Walk with us toward
cooler cities.
Investor, city team, early walker, or press, if you think heat data should protect people, not only optimise traffic, say hello.
HQ: Tallinn, Estonia