The Itinerod Postal Circuit, commonly known as the Itinerod, is an important mail train circuit that crosses the Trans-Antarctic Mountain Range to deliver mail to and from South Pole City. The route was built by Eastshield and Trans-Antarctica. Oil to fuel the mail trains was provided by West Pengolia (Penghis Khan thought the plan sounded PWNsome), and all three states funded the entire project. The Itinerod is operated by both the Antarctic Express and the Penguin Mail Co.