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LiDAR

Use public laser surveys for real roofs and towers, or build the whole model from one.

LiDAR is a laser survey flown over an area, which records the height of everything it hits. Many governments publish theirs for free. The app reads them straight from the publishers and can use them two ways:

LiDAR buildings: Under Layers. Keeps the map data model, but rebuilds each building from its scanned roof, with setbacks, towers, domes, and spires. Buildings no survey covers keep their mapped shape.
LiDAR only: Under Model > Build from. Builds the whole area from the survey as one solid piece in one color, including the ground, buildings, trees, and bridges. It doesn't depend on how well the city is mapped.

Public surveys cover the United States, Canada, much of Europe, parts of Japan, New Zealand, and a few other places. Elsewhere the app says no survey covers the area.

Most of the country or region: Belgium, Denmark, England, Estonia, France, Latvia, Liechtenstein, Lithuania, Luxembourg, Netherlands, New Zealand, Poland, Puerto Rico, Slovenia, Spain, Switzerland, United States (most states)
Parts of it: Austria (Salzburg, Vorarlberg), Canada, Finland, Germany (7 of 16 states, part of Brandenburg), Italy (Trentino), Scotland, Northern Ireland's coast
One city or a small area: Dublin, Genoa, Halle, Montevideo, Nagasaki, Port-au-Prince, São Paulo, Tokyo area, Whitehorse
No LiDAR source yet: Map data models work everywhere.

Coverage is approximate. With an area picked, Survey lists the surveys that cover it. Updated November 2026.

Before generating

LiDAR downloads are large: about 150 MB to 1.5 GB per square kilometer for LiDAR buildings, and from 75 MB for LiDAR only, depending on the survey. Start with a small area, about 1 km across. The app warns when the rectangle around the area is over 1 km².
The first build of an area can take several minutes. Downloads are kept in the browser (up to 1 GB), so building it again is much faster.
On an iPhone or iPad, LiDAR buildings can need more memory than the browser allows, even on a small area, and the page can close partway through generating. The app asks before generating, and Generate without LiDAR buildings builds the buildings from the map instead. A computer can generate the same model with LiDAR buildings.
LiDAR only works best on small areas at a large scale, around 1 km printed 150 to 200 mm across.

Choose a survey

Where several surveys cover an area, Survey lists each one with its year, its density in returns per square meter, and how much of the area it covers. Prefer sets how Automatic picks one:

Balanced: The newest survey, unless it's too sparse for the grid cells and one up to 5 years older (Older by up to) fills them clearly finer.
Newest survey: Always the most recent.
Most detail: The densest survey, whatever its age, unless the newest has nearly as many returns.

A survey picked by hand is read first, and the others fill in where it doesn't reach. LiDAR buildings and LiDAR only share the same pick.

LiDAR buildings settings

Measure: Whole roofs (the default) rebuilds each building from the scanned surface, with its setbacks, towers, and roof shape. Heights only keeps the mapped shape and only corrects heights that are far off.
Roof detail: How finely roofs are read with Whole roofs: a cell size on the print, or on the ground in meters.
Smallest footprint: Buildings smaller than this on the print keep their mapped shape and aren't measured, which saves time.
Prefer LiDAR on conflicts: On by default. Uses a good scan even where it disagrees with the map. Off keeps the mapped building in those cases, which is safer where surveys are old.
Mapped bare rock: Also measures mapped rock, like outcrops and cliffs.

Surveys that come as whole tiles

Some publishers only offer whole files, sometimes hundreds of megabytes each. These are never downloaded without asking. Once the model is generated, a LiDAR to download card says which surveys, how many tiles, and about how much. Press Download and generate again to download them, or Not now to keep the model without them.

Limits

A model shows the city the year it was surveyed. Buildings built since are missing, and ones torn down are still there.
Glass and dark roofs reflect few laser points, so those spots are filled in from around them. Gaps over water are filled from the map's water.
With Water outlines from map data on, a LiDAR only model prints plain ground at the level around it where none of the surveys read has returns. If a survey that comes as whole tiles covers that part, the LiDAR to download card offers it.
LiDAR only models are seen from above, so skybridges and elevated tracks are solid down to the ground.
In a LiDAR only model, the tallest mapped buildings (60 m and up) are checked against the survey. If one is missing or too short, the app reads a survey that has it, or warns about it, and the 3D editor can add it from the map. See LiDAR only models in the editor. This needs Water outlines from map data on.
Some publishers block browsers from reading their files, so a few countries with surveys still can't be used.

LiDAR buildings are free to download when the whole area is inside a green area shaded on the map, and up to 4 km across. Over 4 km, Free and Maker get the mapped buildings instead. A LiDAR only model, or LiDAR buildings elsewhere, require the Pro tier to download. See Tiers and accounts.