Continuing the video game references, Metro-2 is virtually identical to the creepy tunnels found in 4A Games Metro 2033 series. The location is similar too. Said to run parallel with the public Metro-1 system in Moscow, Russia, Metro-2 is a secret underground network that can trace lineage back to Joseph Stalin.
Access to the tunnels isn't necessarily shut off. That's because Metro-2 has become something of a myth more than a fact, and this only adds to the rich intrigue surrounding these abandoned train shafts. Creepily, conspiracy lovers claim Metro-2 connects to the Kremlin by way of the Federal Security Service headquarters.
There are also links to the government airport at Vnukovo-2, and an underground town beneath Moscow's Ramenki District.
It's certainly not the kind of place you'd like to be left alone. If all the above is true, Metro-2 has somehow been kept private. There are even mysterious ventilation shafts close to Moscow University that don't appear connected to the Metro-1 system.