Abstract: A railway boxcar may be provided for transporting packaged products having generally uniform first and second perimeter dimensions. The railway boxcar may include a car body having an interior compartment defined in part by a floor and a plurality of sidewalls. In one embodiment, the floor may include a width which generally corresponds to a multiple of the first perimeter dimension and a length which generally corresponds to the sum of a second multiple of the first dimension and a third multiple of the second dimension. In another embodiment, a door opening may provide access to the interior compartment. The width of the door opening may generally correspond to a fourth multiple of the first perimeter dimension. In another embodiment, a panel assembly may be provided to selectively fill voids within the interior compartment. The panel assembly may include a plurality of elongate plates extending generally parallel with one another.