A roving museum on steel wheels will make its only Iowa stop in the state’s far southeastern corner next week. Dubbed the “Celebrate the Century Express,” the vintage four-car train will hold its grand opening in Keokuk on Wednesday.U-S Postal Service spokesman Richard Watkins says the passenger cars on the Express are devoted to multi-media exhibits depicting the dozens of stamps issued to honor the last one-hundred years.Watkins says the train provides a chance for people to learn about and take pride in the growth and development of our nation — and that includes rail travel. He says the exhibits combine history with high-technology.The train will be open for free tours in Keokuk’s Victory Park on Wednesday from 11 to 7 and Thursday from 10 to 6.