Arsenalna station is located 105.5 meters below the surface, making it the deepest metro station in the world. If you made a vertical shaft on earth as deep, you could drop the entire Statue of Liberty into it and still have more than twelve meters of headroom left to drop other stuff. To board a subway train at this station, commuters have to take two seemingly never-ending escalators to the bottom. The journey takes up to five minutes.
Arsenalna’s unusual depth is attributed to Kiev's geography. The station entrance lies at top of a steep valley next to the Dnieper River whose high banks rise above the rest of the city. Arsenalna’s adjacent station, Dnipro, lies just above ground level close to the river bank before the metro line dives into the ground under Dnieper’s high banks. In order to avoid a steep descent, the Arsenalna station had to be built on the same level which required the station’s entrance to be at the top of the banks, more than a hundred meters above.
The world’s second deepest metro station is located on Saint Petersburg Metro, which is one of the deepest metro systems in the world and the deepest by the average depth of all the stations. The system's deepest station, Admiralteyskaya, is located 86 meters below ground. The Saint Petersburg Metro including Admiralteyskaya has some of the longest escalators in the world, exceeding 130 meters.
The former Soviet Union has some of the most deepest underground metros in the world. Park Pobedy, located on the Moscow Metro, lies 84 meters underground, warranting it the third position in the ‘list of deepest metro stations in the world’. The Moscow Metro is also the deepest in Russia, having a maximum depth of 97 meters.
Yet another contender to the title of the world’s deepest metro system is Pyongyang Metro, in North Korea’s secretive capital city, with tracks lying at over 110 meters underground. Commuters ride down to the Puhŭng Station—one of only two that foreigners are allowed entry— on escalators accompanied by the “sound of revolutionary anthems booming from antique loudspeakers.” The journey takes nearly four minutes.
Because of its depth, the metro stations double as bomb shelters, with blast doors in place at hallways. The metro is so deep that the temperature of the platform remains a constant 18°C all year.
Accoridng to amusingplanet