Apps with coordinates

[Arne Vandendriessche]

Are there downloadable apps that you can use to, for example, enter coordinates of trenches? And that can go to that precise place? This way you can walk the entire front line.

Arne

[Michelle Young]

Great War Digital Linesman package is excellent. 

[Arne Vandendriessche]

Thanks Michelle

[WhiteStarLine]

Hi Arne,

Not quite the same level of sophistication obviously, but if you want to go to a specific point, you can convert it and paste the latitude, longitude into Google or Bing and right click and select 'Navigate to Here'.  That's how I travelled to multiple locations in France in 2018.

[AOK4]

Beware: maps are only maps. They are an interpretation of several sources (often aerial pictures). The trenches on maps may not be 100% exactly as shown and the depth was often a big question mark (fake and shallow trenches spring to mind). There were all kinds of camouflage techniques in use as well as decoys. Transferring old maps to nowadays coordinates may be a few metres off as well. In most cases, reading the ground is more revealing than blindly following a converted trench map coordinate.

Jan

[WhiteStarLine]

I respect AOK4's opinion and posting history but I have a very different view and would encourage Arne or others to pursue his approach.  This response is based on my familiarity with British survey techniques on the Western Front but I think the responses are applicable to other combatants and their mapping techniques.

maps are only maps.

Here are 3 quick examples of the key role maps played:

1. In 1915 a French Groupe Canvas de Tir commandant lamented he had no accurate maps of his trenches as no German maps had been captured for a month.  Maps indicate friendly and hostile dispositions and without a knowledge of these planning is impossible.
2. By 1918 the accuracy of and rapid provisioning of maps to planning staff allowed entire Armies to commence battle with an artillery barrage without pre-registering.  As German gun crews moved locations, sound ranging and topographers cooperated to identify and fire on these new positions using predictive techniques.  One forum post I read somewhere gives a harrowing account of a German survivor watching a fire mission break apart guns and crew, with no target registration to give them any warning.
3. Over 24 million maps were printed and by late 1918, over 21,000 a day were delivered.  This appears to be a good indicator of the demand for maps by those fighting the war.

They are an interpretation of several sources (often aerial pictures).

Sorry, but this is not my understanding of the process.  From the start of aerial photography, it was tightly integrated into the cartographic model.  By 1918, this was a 6 step process, done in sequence.  Note the correlation of data from each technique into the framework:

1. The initial French or Belgian trangulation was checked,
2. Topographers integrated cross roads and other distinctive aerial photo features.
3. Existing cadastral plans were cross referenced.
4. Field surveyors plotted detail not apparent in aerial photographs.
5. Detailed plotting from aerial photographs was used to update the framework.
6. Field contouring data was added,

The trenches on maps may not be 100% exactly as shown and the depth was often a big question mark (fake and shallow trenches spring to mind).

Using Chasseaud's research of over 20,000 positions organised for fire (trenches, redoubts, posts etc), I'm not aware of a statistically significant sample where the cartography deviates from the marginal note "Trenches correct as at ...".  Nor am I aware of a body of trench maps where trench depth is recorded.  I don't know how you would record it for your own forces, given the local variation and I don't know how you would find it for enemy trenches, given the problem of sunlight and shadows as observers flew over highly protected trenches in dangerous conditions.  Happy to stand corrected with any references you might have.

There were all kinds of camouflage techniques in use as well as decoys.

Completely agree.  It is up to the researcher to decide the key trenches that shaped the battle, but this is probably more military history than mapping.

Transferring old maps to nowadays coordinates may be a few metres off as well.

Agree, but more importantly the best standard of the day described what you and I think of as a point location to a locus of points within 25 square yards.  Most references were within a 2,500 square yard bounding box.  Couple this with the fact that a fighting trench has its own length and breadth then any conversion error is probably within the trench boundary anyway.  Having checked conversion errors against a list of 1,000 surveyed points, if you had specified that you wanted to visit every surveyed crucifix on the Western Front, then I would agree.  In this case, individual sheet georeferencing minimises this error almost completely for a 1:10,000 map.

In most cases, reading the ground is more revealing than blindly following a converted trench map coordinate.

Living 20,000 kilometres away, I have only used the technique in 3 trips over the decade to Ypres Salient, Pozieres, River Somme and Hindenburg Line.  Given that over the last century, these locations have since been either settled and developed or ploughed over and sown with multiple crops, I didn't see a great many areas where reading the ground revealed what had happened before.  I have read many accounts on this forum where Linesman users appear to tell me the same story with their approach. 

 

Jan, not having a go at you, just wanting to reinforce my belief in what Arne is trying to do!

 

Cheers.

[AOK4]

WhiteStarLine,

I am not talking about the actual ground layer of the maps, that is more than excellent. I am talking about all the other indications, especially those in enemy territory: bunkers, tenches etc. This is clear to me from my own experience when doing research for my book "Defending the Ypres Front 1914-1918". I have found British trench maps of inferior quality compared to German ones (a lack of regular updates and especially clearing of outdated information in case of destroyed trenches). Interpretation of trenches and bunkers in enemy territory was often very inaccurate: the Flandern-Stellungen were often drawn as very strong trenches, while they were often only shallow and especially locating bunkers was extremely difficult. I have also read reports of reconnaissance patrols to investigate enemy positions which were very much made up (a bit like the mapping patrol in "Blackadder"), resulting in faulty information on trench maps.

That is what I mean with "maps are only maps". They give an idea of the area, but don't expect to find a tench exactly within 2 metres, for that (and that is why Arne wants maps) one has to look at the ground and interpret the ground. There is the area which I know extremely well and where I can point you to trenches and location of former buildings and bunkers exactly because I have been reading the ground for dozens of years. That is also how one finds areas where there is still something to find (and that's what Arne wants to do). Trench maps help, but they are only a part of the research, reading war diaries, books etc and go on the spot are just as important and even more important.

(and the most important thing in case of searching for relics: knowing people who know what has happened to the specific plot of land since 1918, whether it has been thoroughly searched or not)

Jan

[WhiteStarLine]

Many thanks for that and I now understand (and agree with) your viewpoint.  Especially this bit!

52 minutes ago, AOK4 said:

and the most important thing in case of searching for relics: knowing people who know what has happened to the specific plot of land since 1918, whether it has been thoroughly searched or not)