A River in Spain: Discovering the Duero Valley in Old Castile

I found this book a bit heavy on the historic side of things when I first read it. Originally I was looking for a more practical guide to the river and it's communities as part of a canoe trip from Aranda de Duero in Spain to Oporto in Portugal. However, it's been a few years since I completed that adventure and now I'm settling down in the Duero region so the book has become a much more interesting part of my library. This is an incredible part of the world and this book is a good source of information - although an update wouldn't go amiss at this stage...