Scan the Whole Planet
Chris Fisher studies dirt for a living. He’s a professor of anthropology at Colorado State University and a National Geographic Explorer who has spent years flying over forests with lasers pointed at the ground. With geographer Steve Leisz, he founded a nonprofit called The Earth Archive, with an ambition that sounds almost too big to take seriously at first: not one ruin, one park, or one country, but the entire land surface of the planet, rebuilt in navigable 3D before it changes for good.
Why Not Just Protect the Famous Sites?
We already have UNESCO World Heritage lists, national parks, and protected archaeological sites. So why scan every hillside on Earth instead of just guarding places already known to matter? Because most of what’s worth protecting hasn’t been found yet. Old walls, buried settlements, and ancient field systems hide under tree cover and centuries of silt, invisible even to someone standing right on top of them. Protect only what you already know about, and you guarantee you’ll never find what you don’t.
How Lidar Sees Through a Forest
The tool is lidar, light detection and ranging. An aircraft flies low over the land and fires millions of laser pulses straight down. Each pulse bounces off whatever it hits, leaves, branches, bare dirt, and a sensor times the return trip. Combine those timings with the plane’s exact position, and you get a dense 3D map of every surface the light touched.
Not every pulse hits a leaf, enough slip through gaps in the canopy to bounce off the ground beneath. Software isolates just those ground returns and discards the rest, like shaking leaves off a model until only bare earth is left. Fisher has said the method can resolve detail down to about 8 inches (20 cm), fine enough to spot an old wall, not just a hill.
The City Under the Jungle
In 2018, archaeologists Marcello Canuto, Francisco Estrada-Belli, Thomas Garrison, and Stephen Houston flew lidar over 810 square miles (2,100 km2) of Guatemala’s Maya Biosphere Reserve. Published in the journal Science, the survey turned up more than 60,000 previously undetected structures, houses, palaces, ceremonial platforms, and stone pyramids, buried under jungle that archaeologists had walked across for decades without knowing what sat beneath their boots.
Fisher had already felt that shock firsthand. In 2007, working with a team in the Honduran rainforest, he helped trace the outline of a lost settlement now known as the City of the Jaguar, later recognized as a World Heritage Site. After that and Guatemala, scanning an entire planet stopped sounding like fantasy.
A Race Against Time
In a TEDx talk titled “Let’s Archive Everything on Earth, Before It’s Too Late,” Fisher laid out the stakes: rising seas, wildfires, erosion, and thawing ground are wearing down cultural and ecological sites faster than anyone can study them. “The Earth is changing so quickly that we have limited time to create these 3D records that can be preserved for future generations,” he has said. The Earth Archive can’t stop that damage, but it’s trying to capture a complete record of the planet’s surface while it still looks like this, so that a site lost to flooding or fire isn’t lost from the historical record too.
What’s Still Unknown
None of this is finished. The Earth Archive works project by project, piecing together funding and borrowing existing lidar data from countries like the Netherlands, which has already mapped its own terrain. There’s no published global timeline, and some terrain, oceans, ice sheets, dense cities, is far harder to scan than open forest. “The entire land surface of Earth” is the stated goal; for now, it’s a map of however much of it the project has managed to reach.
Why This Sticks With You
It’s easy to assume the age of discovery is over, that satellites and centuries of explorers have already found everything worth finding. The Earth Archive argues otherwise: tens of thousands of structures sat under a forest that people had walked through for generations, and nobody knew they were there. The project’s core insight is simple: there’s probably more hiding in plenty of places we’ve already looked. That’s worth remembering the next time something seems too familiar to still hold a surprise.