On June 13, 1919, ex-RAF pilot C.K. Shepherd rode his Henderson-4 (named "Lizzie") across America, arriving 4,422 miles later in California on August 7th of the same year. It's a fascinating read!
The images above are from an electronic version digitized from, oddly enough, a copy presented to the University of Toronto in 1980 by the Ontario Legislative Library. What the book was doing there will forever remain a mystery. You can download it at the Internet Archive.
In 2010, a blogger named Chris decided to trace Shepherd's cross-country journey on a modern motorcycle. Read his adventures at Across America by Motorcycle.