Nobody knows why it is considered to be possible to go through time and space in places that accumulate energy. Many people are seriously engaged with this issue, and many of them tell stories about their own experiences in time traveling. According to the researchers of such anomalous zones, the deep location of Metro stations is quite likely to provide means of communication with other worlds.
But jokes aside, if you go by Metro from the centre of Moscow to the outskirts, the trip really will be a time travel: from the 1930s to the present time. During your way the stations decorated with marble and mosaics will be replaced by gray and monotonous stations built in the 1980s.