WW1 cave entrance, Rajakylä, Vantaa, Finland

Entrance to First World War 110 m² U shaped cave in base III:9 in [Krepost Sveaborg](https://en.wikipedia.org/wiki/Krepost_Sveaborg) land front defense line in Rajakylä, Vantaa, Finland. The base was built in 1915 - 1918. The whole base contains: * 135 meters of thrench * 3 machine gun positions * 2 observations posts * 12 shelter rooms, one 35 m² room is inside a rock in tunnel * 110 m² cave More info: * [Location in Google Maps](https://goo.gl/maps/duEN1zb8HHBVqjiZ8) * [Wikipedia: Krepost Sveaborg](https://en.wikipedia.org/wiki/Krepost_Sveaborg) * [John Lagerstedt , Markku Saari: Krepost Sveaborg](http://www.novision.fi/viapori/eavaus.htm) * [Finnish Heritage Agency site info](https://www.kyppi.fi/to.aspx?id=112.1000007726) (only in finnish)