Baltimore, which already has a 50-foot channel, has a bottleneck on the land side: the Howard Street tunnel, through which trains have to pass to reach the port, and which is too small to accommodate the double-stacked container cars that are increasingly the standard for rail shipping. The rail line CSX has announced a workaround that could cost hundreds of millions, involving a new yard beyond the tunnel filled with containers brought by truck; the port will load the trains with a single container to get through the tunnel, and the trains can be completed at the yard.