| Using
GPS To Find Ancient Stones
Some ancient stones, such as Stonehenge, can be easy to
find, even in the dark and with your eyes closed! Some
stones, however, can be exceedingly difficult to find,
particularly those in dense forestry, under thick heather or
simply in the middle of no-where. One site already listed, 018
Grey Mare, can be found in a shallow depression on flat
open moorland and despite it being a sizeable boulder is
difficult to see even from a few meters away. A GPS receiver
is an ideal aid for locating ancient stones.
Each stone entry has a 8 figure grid reference, located
in the right hand column of each page. This grid reference
has been calculated from OS 1:25,000 series maps of the area
and is accurate to within approx. 10m. It has also been
checked on location for accuracy using a GPS Receiver. The
GPS Receiver actually gives a 10 figure grid reference but
as accuracy is unlikely to be better than 7 to 15m of the
target location, an 8 figure grid reference has been given
as it is accurate enough for finding most stones.
All you need to do is create a new Waypoint with your GPS
device, change the grid reference to that listed for the
stone you wish to visit e.g. 2137 4350 and give it a
meaningful and unique name to make it easier to remember
where you are heading. There is a suggested easy reference
name on each page. Once near the location, use the GOTO
feature and follow the direction indicator. You should also
set your GPS device to British Grid and Ord. Srvy. You can
also use the GPS GOTO feature to take you to stones when
driving but let some else navigate and keep you eyes on the
road!
Please note that this method will only give you the
direction or bearing in which the target stone can be found,
it is up to you to find a way to negotiate any rivers,
woodland or whatever lying between your start point and the
target location.
About GPS
The Global Positioning System (GPS) is a satellite-based
navigation system made up of a network of 24 satellites
placed into orbit by the U.S. Department of Defence. GPS was
originally intended for military applications, but in the
1980s, the government made the system available for civilian
use. GPS works in any weather conditions, anywhere in the
world, 24 hours a day. There are no subscription fees or
set-up charges to use GPS.
GPS satellites circle the earth twice a day in a very
precise orbit and transmit signal information to earth. GPS
receivers take this information and use triangulation to
calculate the user's exact location. Essentially, the GPS
receiver compares the time a signal was transmitted by a
satellite with the time it was received. The time difference
tells the GPS receiver how far away the satellite is. Now,
with distance measurements from a few more satellites, the
receiver can determine the user's position and display it on
the unit's electronic map.
A GPS receiver must be locked on to the signal of at
least three satellites to calculate a 2D position (latitude
and longitude) and track movement. With four or more
satellites in view, the receiver can determine the user's 3D
position (latitude, longitude and altitude). Once the user's
position has been determined, the GPS unit can calculate
other information, such as speed, bearing, track, trip
distance, distance to destination, sunrise and sunset time
and more.
Important Notice
Ancient Stones cannot accept any responsibility for the use
of this data, the use of any GPS unit, map or compass in
conjunction with the data, or any errors which may be
present in the data. Obviously we will be interested to hear
of any such errors or any other suggestions as to the use of
the data. The data should not be your sole aid to
navigation, which should always rely on the correct map for
your day, a good compass, and the knowledge of how to use
them.
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