Co. Houston's trucking industry is well-integrated with the Port of Houston, Houston Intercontinental Airport, Hobby Airport, Ellington Field, and the mainline railroads serving the city. Each draws from the others while supporting the others. Cargo arriving at the port is trucked inland.
Planes arriving at the airports discharge their freight for trucks to deliver in the city.
Freight discharged at the railhead is trucked elsewhere. The system works in reverse as well, with trucks bringing cargo to the port, the rail lines and the airport for shipment.