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The Moscow Metro (Russian: Моско́вский метрополите́н, tr. Moskovsky metropoliten) is the underground transit system used in Moscow. It prominently features a Moscow Metro M outside its stations, one of which gets stolen in Mario is Missing! (though, alongside Lenin's Tomb, it appears only in the game's DOS and Deluxe versions). This theft causes the entire metro to close down until the sign is returned. Luigi, while traveling through Moscow, takes back the sign, and through the metro's information booth, returns it to its rightful place and restores the metro. However, the booth's receptionist requires him to prove that the sign is genuine, which he does by answering the questions below:
The Moscow Metro is the city's underground train system. The Metro is world famous because of its luxurious stations. Riders wait for the trains surrounded by chandeliers, precious metals and a lot of beautiful marble. Each of the 132 stations is decorated differently, and some even include museums! The Metro was built in 1935 by the dictator, Josef Stalin, and is still the fanciest underground train system in the world (of course, there's not much competition). Each entrance is marked with an enormous red M.