PURPOSE: To carry out a cargo work of the railroad freight three-dimensionally without changing locomotives by providing a means to move an aerial line provided above a rail laterally and horizontally, and a crane.

CONSTITUTION: In a freight yard provided in the premise of a railroad freight station, a means to move an aerial line 16 provided above a rail 6 laterally horizontally, and a freight crane 26 are provided. The contact surfaces 34 and 36 of the aerial line 16 to move horizontally and the fixed aerial line 17 which does not move are formed oblique, and when the aerial line 16 advances horizontally, the contant surfaces 34 and 36 are contacted to feed the power from the aerial line 17 to the aerial line 16. When an aerial line holding plate 20 is moved back horizontally and housed in a groove 22, the aerial line 16 is moved rearward, and there is no obstacle above a freight train 8. Therefore, the crane 26 is lowered from the position B to pick up a container 10, and to move it to the position C, where the container 10 is placed in the unloading zone 32. And a new container 10 is loaded from a loading zone 30 at the position A, the crane 26 is lowered from the position B, and the container 10 is loaded in a freight train 8.