The Finnish authorities explain the operating concept of a network of underground tunnels to the country's civilian population, Wall Street Journal reports. The decision was made in response to military exercises by Russia on the border with Finland.
The infrastructure is located near Helsinki, and the total length of the tunnels is about 200 kilometers. Underground routes connect a single network of shopping centers, parking, electricity and water supply lines.
Separate tunnels will be used only by the military for unobtrusive movement between the home stations of various units.
The entrances to the tunnels are closed with doors made of a special metal alloy capable of withstanding an explosion. The site premises were planned in such a way as to accommodate all 600,000 inhabitants of the Finnish capital.
Zapad-2017 joint exercises by Russia and Belarus will be held from September 14 to 20. 13,000 military personnel will take part in the maneuvers. The training exercises will be the largest since the end of the Cold War. NATO has repeatedly criticized the forthcoming exercises.