To provide a sleeper which can prevent an ice lump from colliding against railroad installations including a driving shaft and wires for signals, arranged between rails on a railroad, even if ice and snow splashed to a bottom surface of a train and adhering to the same as lumps, are dropped to hit the railroad installations during traveling of the train in cold climate areas.

The sleeper has a sleeper main body 1 of a rectangular parallelepiped, and a slope surface 4 formed on an upper surface of the sleeper main body 1 and having an up-grade in a train traveling direction. The slope surface 4 has a plurality of projections 3 formed thereon, which are shaped like pyramids. The sleeper main body 1 is arranged behind the rail driving shaft and the wires for signals, that are set between the rails on the railroad, along the train traveling direction.

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