About 500 feral dogs live in the Moscow subway.
They have figured out to ride from station to station on the trains. Apparently, they are able to ride the escalators, know how long the train will spend in the station, can understand the names of destinations announced on the loudspeaker, and can smell when they've arrived at their chosen stop.
The dogs prefer to ride in the front or back cars, where it's quieter.
The subway dogs are well-fed. Besides scavenging in the garbage, they have learned to send the smaller, cuter dogs out to beg food from the human commuters.
One of their favorite games is to jump into the train at the very last second, just as the doors are closing--hopefully without losing their tails.
A feral dog named Malchik lived at the Mendeleyevskaya station for three years, protecting the station from drunks and other stray dogs. Then, in 2001, he was stabbed to death by a woman named Yulia Romanova, apparently because he barked at her Staffordshire bull terrier. It later turned out that Romanova had a long history of cruelty to animals. After a huge public outcry, she was arrested and had to undergo psychiatric treatment. In 2007 a statue of Malchik, entitled "Compassion," was erected at the entrance to the station.
Passersby like to rub the statue's nose "for luck."