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Dutch - RD Benchmarks Locationless (Reverse) Cache

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Hidden : 12/1/2002
Difficulty:
1 out of 5
Terrain:
1 out of 5

Size: Size:   virtual (virtual)

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Geocache Description:

The hunt for Dutch RD Benchmarks...   

The Netherlands have a long tradition in cartography. Already in the 16th century Dutch cartographers made detailed maps of the Netherlands, used for militairy purposes and for designing, controlling and maintaining the coastline, dikes, waterlocks, bridges, canals, rivers, etc.

Detailed and systematic cartography started in the days of the Napoleon, in 1806 the Topographisch Bureau of the Depot-Generaal was founded. In the year 1815 this service was called the Dienst der Militaire Verkenningen, which was called the Topografische Dienst in 1932.

The coordinate system used in Dutch cartography is called the RD grid (Rijksdriehoeksmeting). The main reference point for this system is the Onze-Lieve-Vrouwetoren, a big churchtower in a town called Amersfoort. Because this is a town in the heart of the Netherlands, the coordinates of this tower are not 000000 / 000000 , but are offset so the coordinates of this tower are 155000 / 463000. This implies that the crossing of the X and Y axis is somewhere to the south-east of Paris.

The Onze-Lieve-Vrouwetoren was the main reference, but not the only one in the Netherlands. Many landmarks are used as triangulation / reference benchmarks: often church towers, water storage towers, lighthouses, monuments, metal benchmark pins in roads or even benchmark pillars. All these points have something in common: these are situated on a geological stable underground and have a clear view around for triangulation. Some pins even have a black and white circle around so these can be used as a reference in aerial photography.


Your task here is to log any OFFICIAL RD benchmark in the Netherlands. These points are marked on the Dutch Topographical Map with:
* a dot with the text RD = a metal pin in the road
* a small triangle with a dot in the heart = a concrete pillar in the ground with a metal pin as reference point
* a circle with a dot in the heart = a huge tower
* a circle with a dot in the heart and a cross above = a church tower
* a blue circle with a dot in the heart = a water tower
* a star with a dot in the heart = a lighthouse

For approval publish:
* the coordinates you measured in WGS-84 format (hddd°mm.mmm) and in RD grid format, use the average mode of your GPS to enhance the accuracy, you should be very precise
* also the catalog coordinates, if possible (there are lists for that purpose, these are not easy to get)
* the elevation you measured (in meters), under or above sealevel
* the kind of object
* the name of this object, if applicable
* the quality and stability of this object
* Upload a photo with the reference point and you and / or your GPS as proof you have been there.

Additional Hints (No hints available.)