I bought this book to research westward immigration. It is fascinating and easy to read. Very little has been written on this subject, and being a California history buff, I found it very informative. I learned new stuff about both the Bidwell and Donner-Reed parties, and about Kit Carson, Jedidiah Smith, John C. Fremont, and the Spanish Conquistadors. The first half of the book concentrates on horse and wagon travel, whereas the second half focuses on the railroads. I would have preferred more of the former and less of the latter, primarily because a lot more has been written about the railroads. The book contains two helpful maps; I would have liked more. All in all, I found this readable and informative.