Because there seems to be no end to new scans, we have decided on a (relatively low-scale)  reshuffle of some maps available via sub-pages. For this reason, some files, such as German maps, will not be available for the next several days, although they might be already accessible via pull-down manu on Mapster. Please bear with us, what comes out should be a little bit more organized than what came in!
In the meantime, we have also added 34 new sheets of a German 1:800 000 map (this type, was replaced in mid-1920s, by the 1:500,000 and 1: 1 mln scale maps), plus 13 new scans of  German 1:25,000 photomaps (Bildplan). This means the source of those maps at the Poznan university is almost dry (a couple of scans will be added soon). Other sheets, approx 1,500 + will need to be acquired from other sources, which is difficult. We do not expect to have any more sheets of this map type by the end of this year.

18 sheets of WIG 1:100,000 maps have been added. They include older variants, from 1920s, from the area of Kresy, and newer editions. from 1930. All sheets available in 300 dpi and 600 dpi. New maps have been marked with a green "New" bubble on the lists.
We have also added approx. 30 scans (600 dpi), to the collection of German air photo maps (Bildplan edition) courtesy of archiwum Wydziału Geologii i Geografii UAM in Poznan, Poland. Majority of those sheets have already been made available in 400 dpi, but this wasn't good enough, so all will have been re-scanned at 600 dpi. We expect around 170 – 180 sheets (in total) from the same source, but please bear with us, as scanning might take some time, perhaps another 2 - 3 months.
Courtesy of the University of Chicago Library we are able to show 230 scans of the Red Army General Staff maps of Eastern Poland, dated 1939, scale 1:25,000. The maps cover the area of Polish Wołyn (Volhynia) and they were produced, probably, in preparation of the "liberation" of the area in late 1939. The maps are a slight re-scale job of the tsarist, topography survey sheets, so-called half-verst maps (1:21,000), with no evidence of updating. Therefore, it should be assumed they are accurate as per the date shown in the top-left corner, i.e. approx. 1885 – 1905. These maps are rather important, as, in many cases, they are the only detailed map of a given area until, at least 1940.
We don't know the total number of sheets produced in this "block", there could be, up to 600 sheets printed in 1939. Another set of scans, around 100 strong, could become available in the next 2 months.

We have added to Mapster the following scans: 83 sheets o German  1:100,000 map (Karte des westlichen Russlands) and 84 sheets of Austro-Hungarian 1:75,000 map (Spezialkarte). all files are available in 400 dpi and 600 dpi.

• Current (up-to-date) list of German KdwR sheets in Mapster
  

• Current (up-to-date) list of Austro-hungarian Spezialkarte sheets in Mapster

Some sheets present different editions of the maps already available, but others fill in the "blanks" of the index sheets.
Nearly all German editions, and about half of the Austrian maps come from the collection of the map division of the Library of Congress, and we have received them due to hard work at the library done by  people involved in  Topographic Maps of Eastern Europe project - thank you very much!

We would like to thank the University of Greifswald for a permission to display scans from their map collections via Mapster. We have currently added:
358 scans of Soviet maps, scale 1:100,000, from 1930s and 1940s,
and
25 sheets of a 1:1 M map in the International Map of the World system
All maps are available as 300 dpi scans. 
Please note: index sheet for the 1:100,000 maps covers a large section of Europe, so it takes a long time to load!
By the end of the year we should have added  a few dozen maps to the above map sets, this time from a private collection. Early next year we plan to populate the index sheet of the Soviet 1:50,000 map with approx. 900 scans from Greifswald, and add about 50 more sheets from private collection.

166 sheets of a WIG 1:100,000 series have been added, all 300 dpi & 600 dpi (Mapster index sheet). These are older editions, dated 1920 – 1925, from private collection. Please note! - map sheets from the area of "Kresy" (Borderlands), approximately east of Pas 42, which cover the area of Russian 2-verst map (1:84 000) – do NOT exactly correspond to the later WIG editions, even though they might have the same sheet name - and the discrepancy grows the  further to the east a sheet is from the Pas 42. This WIG index sheet dated 1924 (approx. 8 MB) might help to see the issue clearly. Therefore, a list of WIG 1:100 000 maps has been split into the older editions and the newer ones. The sheets now added have been marked on this list,  available through Mapster.
Because the new sheets are based on Austrian German and Russian original maps, they might appear, at first sight, to be quite primitive. The most typical change is the updated place-names (in Polish) or Russian (Cyrillic) changed into Latin. That said,  some sheets are quite impressively redone such as a multi-colour Mir-Stołpce. These early editions, even though somewhat crude perhaps, are really valuable, as they show the area right after "Great War", as WW1 used to be known at that time. Moreover, sheets extending far into the territory of what would be the Soviet Union, mark the hamlets of Polish impoverished gentry (zaścianek, zaścianki), which disappeared from later map editions. For those familiar with Polish, the sheets offer a bewildering array of place-names which, although mostly of Polish origin, actually make no sense in contemporary Polish, and more akin to Jabberwocky, e.g. Dzirkal, Smacz, Czeremoszniki Podzisienne, Ażubel, Nunniki, Chrapunia, Ergał, Azopniki, Zaścianek Usoch (Zahibel), Uroczysko Baby-Woda, Uroczysko pod Winpiszczem, Folwark Stary Zamek-Birża, Dwór Smolgów or Błoto Lodowe Jezioro.
Two sheets of WIG 1:500,000 maps, sheets Przemyśl and Wiedeń (Vienna), have also been added, both in "temporary edition", dated summer 1939.
Another, minor update is 10 sheets of Russian 2-verst map (1:84,000) from Latvia, and one from the Ukraine (Zhytomir). A larger number of those maps can be expected next year.