Hautes Fagnes, Belgium · 14 – 17 August 2026
It burned on a high peat plateau on the German border, for three days, across an area fourteen kilometres wide. Every point below is one measurement of heat on the ground. Press play to watch three days pass.
hectares, as reported by the Walloon authorities
from first measurement to last
separate measurements
every Belgian fire on satellite record
Belgium is not a country that has wildfires. Since satellite records begin in 2001, the largest previously measured was 884 hectares of heathland near Wuustwezel in 2021. This was several times that, on any measure.
These bars are satellite upper bounds, not surveyed areas, and they run high. The method draws a circle around every hot pixel and merges them, so a scattered fire measures larger than it is. For this fire the method gives around 7,100 hectares against the 3,000 reported on the ground: a factor of more than two. We publish the measurement and the gap rather than quietly picking whichever number reads better.
The comparison itself holds, because every bar is computed the same way from the same archive. The absolute numbers should be read as a ceiling.
how it was found
Two clocks matter here, and they are not the same: when a satellite measured the heat, and when that measurement reached us. Only the second one can set off an alarm.
Meteosat, parked above the equator, registers 18 megawatts on the plateau. On its own that is nothing - a bonfire, a hot roof, a false alarm.
A polar satellite passes overhead and sees the same spot sharply. Two instruments, two orbits, one location. It is real.
The Meteosat measurement reaches our database, thirty-eight minutes after it was taken. The sharp polar measurement from 14:02 does not arrive until 17:16, so the coarse view buys nearly three hours.
Within ninety minutes the measured output has multiplied nearly tenfold and the fire covers several pixels.
The strongest reading of the fire: 1,355 megawatts of radiated power.
After seventy-three hours nothing warm is measured any more. Peat, though, can smoulder below the surface long after the satellite stops seeing it.
two kinds of satellite
Meteosat never looks away but sees roughly - kilometres per pixel. The polar satellites see sharply, a few hundred metres, but only pass overhead a few times a day. Neither is enough on its own.
Seeing is not knowing. Meteosat saw the fire twenty-two minutes before the polar satellite did, but its measurement also travelled faster: it was in our database at 14:18, while the sharp one landed at 17:16. On this fire the coarse view was worth almost three hours, and that is the gap an operator actually feels.
why here
The Hautes Fagnes is a high moorland plateau straddling the Belgian and German border, and Belgium's highest ground. It is peat: partly decayed vegetation that has been building up in waterlogged conditions for thousands of years. Peat that holds its water is hard to set alight and harder to keep alight, so it takes a sustained dry spell before a fire will carry across it.
That is what makes a fire of this size on this ground unusual rather than merely large. It is also why the end of a peat fire is harder to call than the end of a grass fire: peat can smoulder below the surface for weeks, giving off too little heat for a satellite to see, and reappear when the wind picks up.
The nearest towns are Eupen, twelve kilometres north, and Verviers, nineteen kilometres north-west. Aachen lies twenty-seven kilometres away across the German border.
