SVG Map of fortresses around Liege in Belgium (source: <a rel="nofollow" class="external autonumber" href="http://www.demis.nl/mapserver/mapper.asp">[1]</a>) Blue indicates forts constructed 1888-1891; those in red were constructed in the 1930s.
<ul><li><a href="//commons.wikimedia.org/wiki/File:Festungsring_Luettich_Karte.png" title="File:Festungsring Luettich Karte.png">Festungsring_Luettich_Karte.png</a>: Demis project</li>
<li>derivative work: <a href="//commons.wikimedia.org/wiki/User:Grandiose" title="User:Grandiose">Grandiose</a> (<a href="//commons.wikimedia.org/wiki/User_talk:Grandiose" title="User talk:Grandiose"><span class="signature-talk">talk</span></a>)</li></ul>
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