LiDAR maps in Denmark

Last updated: 23 August 2026

A LiDAR map shows the landscape as it looks without trees, buildings or vegetation — just the bare earth itself. For a detectorist it's one of the most powerful ways to read the ground: barrows, hollow ways and old field boundaries that are invisible on an ordinary aerial photo stand out clearly in the raking light. Here's what a LiDAR map is, what it reveals, and how to use it to find ground worth walking.

What is a LiDAR map?

LiDAR (Light Detection and Ranging) is a survey in which an aircraft fires millions of laser pulses at the ground and measures how long each takes to return. From that you build a dense elevation model of the whole country. Strip out everything that isn't the ground itself — trees, buildings, vegetation — and you're left with the bare earth: the terrain on its own.

A hillshade takes that model and lights it from a low angle, so every small ridge and hollow casts a shadow. It's exactly that combination — bare earth plus shading — that makes small human-made traces in the landscape visible, including ones the eye would never catch out in the field.

What LiDAR reveals in the terrain

On a bare-earth hillshade, shapes leap out that neither an aerial photo nor a look across the field would show:

• Barrows — even an all-but-ploughed-out mound can leave a low, round rise the shading picks up.
• Hollow ways — old, worn-down routes read as parallel grooves running through the terrain.
• Old field boundaries and field systems — ridge-and-furrow and vanished boundaries trace patterns across today's fields.
• Ringworks, dykes and building platforms — the edges and banks of structures long since gone.

Not all of it is ancient — drains, modern plough lines and forestry work show up too. But the trained eye learns to tell them apart quickly, and a shape worth walking to is often only visible here.

LiDAR map or aerial photo?

An aerial photo shows the surface: crops, grass and tree canopy. A LiDAR map shows the ground beneath. The biggest difference is woodland — where the aerial photo stops at the canopy, some of the laser pulses find their way between the leaves all the way to the forest floor. Ground that looks like impenetrable scrub from above can therefore reveal mounds and traces on LiDAR.

The two maps are strongest together: use the aerial photo to see what's on the ground now, and LiDAR to see what lies in it.

Denmark's elevation model — the official data

The LiDAR map in Muld isn't a third-party service. It's Denmark's elevation model (Danmarks Højdemodel, DHM) — the nationwide height model the state itself collects and publishes through the Danish Agency for Data Supply and Infrastructure. It's the same official data that authorities and archaeologists use. Muld pulls the bare-earth hillshade directly and draws it on the map, so you needn't download large datasets or learn a GIS program.

LiDAR terrain in Muld

In Muld, LiDAR is a layer you switch on over the map: the bare-earth hillshade, ready to pan and zoom in the field. You can combine it with historical maps and protected zones, so you see both the traces in the terrain and where you're allowed to go. LiDAR terrain is part of Muld+.

From map to field

A LiDAR map points you to places worth investigating — but it doesn't change the rules. A low mound on the hillshade might be a protected ancient monument, where detecting is banned on the monument itself and within 2 metres of it. And however promising the terrain looks, you need the landowner's permission before you start.

Muld draws both cadastral parcel boundaries and protected zones on the same map as LiDAR, so you can go from "that looks interesting" to "I'm allowed here" without switching apps. See also our full guide to the rules for metal detecting in Denmark.

Official sources

This page is a plain-language introduction — not a technical manual, and not a substitute for the sources themselves. If you want to go deeper into the data or the rules, go to the official sources.