Control points

Control points and their coordinates and elevations define in practice the reference system for coordinates and elevations used in Finland.

The NLS benchmark register contains information about nationwide control points and benchmarks. The marks are mainly horizontal and elevation control points in classes 1–3 measured by the National Land Survey of Finland.

The product belongs to the open data of the National Land Survey of Finland. More information: Topographic data and how to acquire it http://www.maanmittauslaitos.fi/en/maps-and-spatial-data/expert-users/topographic-data-and-how-acquire-it.

Purpose:

Control points can be used as starting points in surveying and as anchor points in coordinate and height transformations.

Geographic location
Entire Finland
Responsible party

National Land Survey of Finland

Scale
10000
Spatial representation
Text or table
Spatial representation info
Geometry only
Data content

The control point data includes the coordinates (coordinate reference systems: EUREF-FIN and KKJ = the national grid coordinate system) and the elevation of the points (height systems: N2000 and N60) as well as their attributes.

Maintenance

The control point data is updated and maintained continuously.

Lineage

Earlier, the method used for determining horizontal control points was triangulation but now satellite surveying is used. The elevation control points have been determined by levelling. The dataset Control points contains points with different levels of accuracy; the information about the accuracy class is included in the control point information.

Conformity
2011-02-22
The product does not meet the specifications.
Distributor

National Land Survey of Finland customerservice@nls.fi

Limitations on access

no limitations to public access

Reference system
ETRS89 / TM35FIN(E,N) (EPSG:3067)
KKJ / Finland Uniform Coordinate System (EPSG:2393)
N2000 height (EPSG:3900)
N60 height (EPSG:5717)
Distribution format
csv-file
Not based on a decree