In the early 1970s, Princeton University launched a program where incoming freshmen would hike together in the wilderness to get to know each other before classes started. This quickly became popular among American universities, and over the years a large body of collective experience arose. THE BACKPACKER'S FIELD MANUAL was conceived as a compendium of advice for guides leading hikers through America's state and national parks. It was written by Rick Curtis, director of Princeton's program for many years.
When I first heard of this book, I imagined it would be a survival guide, but in fact, the book generally covers the mundane aspects of walking a trail instead of what to do if something goes horribly wrong. The sort of advice you'll find here is what food to bring along to cook for a group of people with diverse diets (including vegans and Jews who keep kosher), how to use a camping stove, where to dig latrines and how to avoid bears. There's exhaustive guidance on Leave No Trace hiking. But even if you aren't leading a big group, there's plenty of information to interest you. The explanation here of how to use a sighting compass is the most clear of any of the guides I've read to date, and the comparison of down and synthetic fabrics has more information to help you choose than some other resources.
As the guide was written for an American audience who were hiking within the US, all measurements for e.g. food are not metric, which limits a bit the usefulness of this book for people traveling internationally.
It's still good to go on and read a real survival manual after this, like the SAS Survival Handbook, as Curtis stops short on many useful tips. For example, he only briefly mentions the building of shelters and does not even describe how to make a snow shelter. Still, this book is full of practical advice and budding trekkers are sure to learn something from it.