D. Appleton & Company, in New York, published a series of travel guides in the 19th century, including `Appleton's General Guide to the United States', a book documenting the US railroad system in 1879 amongst others. British railway enthusiast Michael Portillo takes his copy of the guides around the United States and discovers new places. Along the way, Portillo stops at significant historical sites, exploring the little-known past of specific routes and how they influenced the each country's transformation and growth.