The most important data available on Cetopo is arguably the terrain data. It provides unprecedented coverage, ease of use, and accuracy.
The data is sourced from the excellent Elevation Model 2m by the NLS (National Land Survey).
As the name implies, the Elevation model 2m offers a world class 2x2 meter grid accuracy.
The Elevation model 2m data-set covers almost all of Finland. Some areas are yet to be measured. Approximately 40.000 km² of data is added to it each year according to the NLS.
Some of this is new areas, and some is an update to old areas.
For up to date information about technical details, please visit the NLS page.
A 2x2m grid is dense enough to accurately capture all major terrain features such as hills, roads, fields and lakes.
It also shows smaller features like mounds, paths, ditches and cliffs with decent accuracy.
Any features smaller than the grid, such as rocks, crevaces and small pits, have a risk of not showing in the data.
Steep gradients, such as cliffs, are smoothed out by the grid. For example, a vertical drop of 5m might show as a 70° slope instead.
The Elevation model describes the terrain.
All buildings and structures like bridges have been removed from the laser scanned data.
The model is not as strong in urban areas, where small vertical discontinuities like platforms, elevated sidewalks and terraces are common.
Such details will be smoothed out in the data.