The Underground Phaeton is a secret Russian transportation network that runs from underneath a military base in Mount Elbrus. It can travel to Ekaterinburg, Kabul, or Karachi.
Despite looking like an ordinary phaeton, it is actually rocket-powered, allowing it to travel the large distances in less than a day (Passepartout estimates it travels at over 200 miles per hour). Passengers must wear dark sunglasses and be strapped in at all times.