"Topo Maps" Topic

This topic TMP link got me thinking about how thee are made.

I know nowadays, or at least 80s era, when I visited the Canadian Military's Mapping and Charting Establishment that much use is made of aerial photos and computer programs.

Stupid arsed question

Did they do it the same way for WWII (minus the computers, I expect)? It must have been a monumentally expensive undertaking and the maps themselves, i bet were very expensive.

What about WW1?

I remember when I was on exercise in W germany in the 80s, the topo maps there were far, far more detailed than the Canadian ones we used over here (which were, nevertheless, excellent).

"the maps themselves, i bet were very expensive"

There is a saying in the mapmaking community here: "Anyone can afford a map, provided the Queen buys the first one"

"far more detailed than the Canadian ones"

Of course, there's a lot more Germans and a lot less Germany than in the Canadian case. Probably a lot more details, too. "Yup, ya got some woods here, and over here there's…woods. And hey, more woods."

Varied by nation, but the Brits certainly used a lot of aerial photography, and put serious resources into map-making, especially in NW Europe.

Topos were still a developing art during WWI, and required land survey work.

Aerial survey would have been very much a spot affair at that time, as cameras were still fairly bulky. Real aerial land survey didn't start in the US until after WWI, usually in the late 20's or early 30's. Initially used by county-level authorities for planning purposes, aerial photo surveys were also being used by the USGS to augment and update their land-surveyed topo maps.

I know the British were also doing extensive land surveys, but I couldn't tell you offhand when they started incorporating aerial photos into the work. I know even less about Europe's survey history.

Before there were airplanes, geodesic survey (triangulation). A lot of the contours were filled in with guesswork.

With airplanes (after a while), stereoscopic techniques.

A quick Google search (or Wikipedia) will reveal plenty of information.

Sorry, "geodetic" not "geodesic."

Any sensible country stocks up on maps of its potential opponents *before* wars start. So I bet all the major protagonists of WWII started with quite detailed maps of all their neighbours.

I believe Soviet Russia tried hard to keep its maps secret (civilian as well as military) precisely to limit the opponent. It's doubtful whether this didn't hurt them more than their opponents, who still had detailed maps from 1918.

Some quite detailed topo maps dating prior to 1914 can be found on-line.

In the area of horizontal accuracy (absolute more then relative) in the 1980's captured German WW2 maps were considered to be more accurate/precise then the best satelite imagery tools of the day. I won't comment on today's order of precedence but a friend and co-worker would spend beau coup computer time to get a number then consult the maps and use the numbers from those. As late as the end of the 1990's lead time for a non-crisis 1:50K Topo map by a certain imagery and mapping agency was around a year minimum.

Gracias,

Glenn

I own several 1/5.000th topo maps from WW1 made at
various dates (the earlier being from Spring 1915)
and showing precisely trenches, barbed wire fields,
as well as light railways line, supply pits or arty position.

These wartime maps (arty canvas) were developped from enlarged pre-war French army 1/20.000th "military
staff maps" including 5 meters contours, and were
updated regularly from ground and aerial observation.

In pre-war days, railroad survey parties used the 1/20.000th to locate possible railroad right of way,
before actual building began (with the help of more detailed 1/2.000th maps)
They had to ask permission from War Secretary to use
maps from the area they had been chartered to build
through and hand them back after use.

Given the tight standards of rr construction in
relation with track grades (in Europe, 1% for
mainline, 2% for light /mountain railways as a
common rule for maximum grade), such maps had to be accurate, since a mistake in right of way location
could result in huge increase of surveying
expenditure when eventually found out.

I've been using these 1/5.000th maps to find old
trenches (including narrow communication trenches),
large dugouts and fortified strong points near my
home for years with always 99% accuracy regarding the location of such features in relation with regular topo features like hedges, lone trees, roads, paths,
buildings, etc…

Modern engineering parties also use them to know where
to clear possible shell/ammo piles or underground
cavities before housing developpment begins.

As a side note, it's amazing to see how little the
French landscape (land tract borders, roads, farms,
hedges, wood copses) has actually evolved since
the 1910's, even in the highly mechanized farming
areas of northern France where West front WW1 battles
took place.

"As a side note, it's amazing to see how little the
French landscape (land tract borders, roads, farms,
hedges, wood copses) has actually evolved since
the 1910's"

In researching my Great Uncle's involvement in WWI and the circumstances of his death – I have compared the maps & air photos published in the regimental history with the same area on Google earth – and I agree with Marcpa – that it is absolutely amazing the level of correspondance. The village dimensions, roads, woods are all pretty much the same.

Kurt

Kurt and Marcpa, thanks.

Crumbs, that's brutal. I did a lot of surveying in Banff in 1984 as part of my civil engineering degree and, well, it just staggers me the effort that must have gone into these things without relying on huge amounts of aerial photography.

We children of the late 20th century are so spoiled, I think!
--
Tim

Ditto Bird

Not that this is relavent to WWI – I do know when I was doing geomorphology in the early 1980's as part of one of my geology degrees – that topographic work was done primarily from air photos & stereographic projection which was spot checked by field reconnaisance.

Totady I make subsurface geologic maps as part of my work for an engineering firm and even when locating seismic and well locations that there is still a certain amount of slack regarding well locations, survey plats, land grids, etc -- sometimes on the order of a couple 100 ft. even when using GPS – that is mostly a function of which projection is bveing used or when merging data of various vintages.

Of course with GPS – there are many errors associated with typos in tabulated data.

Kurt

"I believe Soviet Russia tried hard to keep its maps secret (civilian as well as military) precisely to limit the opponent"

I'm sure you're right, but it bears pointing out that if U.S. military maps had as much info as Soviet maps, they'd be classified too.

I was amazed that in the Balkans in the mid-90's, most of the U.S. maps referred to Wehrmacht 1943 mapping data in the small print on the bottom.