How SombraMap
finds the shade.

1. 01STEP

   Build the city in 3D

   We build a real, three-dimensional model of the city — not a flat map, but every building standing at its true height. Some cities we know down to the fine detail of individual rooftops; others we model a little more broadly. Either way, the result is the same: a faithful sense of what actually casts shadow onto the streets you walk.

2. 02STEP

   Find the sun

   For the exact moment and place you care about, we work out precisely where the sun sits in the sky — how high it is and which way it's coming from. It's the one part of this that's pure, settled geometry, so we can be exact. No weather, no clouds, no guessing: just the real position of the sun over your rooftops.

3. 03STEP

   See where the shade falls

   Put a real 3D city under a real sun and the shadows fall where they fall. A low morning sun throws long shadows; high noon throws short ones. We work out the whole pattern of shade across streets, squares and sidewalks for that instant — and when you move the clock, the whole map shifts with it, which is exactly what the homepage's "scrub the day" view lets you feel.

4. 04STEP

   Walk you through it

   Then we find you the way. Knowing where the shade sits at your departure time, we look for the coolest sensible walk from A to B — one that trades a little extra distance for a lot more shade, rather than marching you straight through the glare. Exactly how we pick that route is the part we keep close, but the promise is simple: you get the good side of the street.

A note on precision: the sun math is always exact — where shade accuracy varies is in how well we know a city's buildings. Some cities we know to the centimeter, so the shadow map is sharp; others we know more roughly, so the edges are softer. We're upfront about that difference per city rather than promising one blanket number.