Two of the largest US railroads, Union Pacific and Norfolk Southern, announced on Tuesday a plan to combine in a $72 billion deal that would create America’s first transcontinental freight railroad.

Union Pacific Corporation announced it will acquire Norfolk Southern Corporation, forming the first coast-to-coast rail network in the U.S.

The merged company plans to establish a rail network spanning 43 states, which would be the first transcontinental railroad in the U.S.