Remains of First World War wooden shelter room in [Krepost Sveaborg](https://en.wikipedia.org/wiki/Krepost_Sveaborg) land front defense line from base XXI:6 Oulunkylä, Helsinki, Finland. Wooden Shelter room built in 1915 - 1918 is completely decomposed but the place and part of the trench is clearly visible.
More info:
* [Location in Google Maps](https://goo.gl/maps/FvddG7TCM5Ut97qw9)
* [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=112.1000013764) (only in finnish)