Pretty good for a 48 - page book. It discusses German, French, Soviet / Russian, US, and British railway artillery and that of some relatively minor countries such as Finland, Italy, and Belgium. Perhaps not too surprisingly, the most detailed discussions are on German and French railroad artillery. There is also some fairly detailed discussion Russian / Soviet railroad artillery. The text covering British and American railroad artillery is pretty shallow. The coverage of Russian / Soviet artillery offers much new information that I had never read before, although photos of the major large caliber (305 mm) guns was sparse. This is not an in-depth study of any particular gun, but a series of profiles of what each country had or built in the way of railway guns for WWII, in that direction the large caliber 340 mm, 370 mm, 400 mm, and 520 mm heavy French railroad artillery only received a few sentences of discussion and little information was offered on the performance characteristics of the either guns or the mountings. Very little information was provided on the American and British 14 - inch, 16 - inch, and 18 - inch artillery. This will not be that useful to people that have accumulated large amounts of specific data, but for someone just getting into railway guns, it is and excellent introduction.