Tunnel in WW1 base, Ala-Malmi, Helsinki, Finland

Tunnel and trenches in First World War base XI:2 in [Krepost Sveaborg](https://en.wikipedia.org/wiki/Krepost_Sveaborg) land front defense line in Ala-Malmi, Helsinki, Finland. The base was built in 1915 - 1918. This base build in the hill of Ormusmäki has rare combination of caves and trenches in the same hill. Caves are build under the trenches and there are entrances from threnches to the caves. The whole base contains 4 caves: the 23 m² tunnel in this model and another 85 m², 20 m² and 23 m² caves . More info: * [Location in Google Maps](https://goo.gl/maps/tRFvMkRRfcoRaJ548) * [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=112.1000013430) (only in finnish)