Is this really the first guide?

Though Walden is visited by more half a million people from around the globe each year, and though many guides have been written about Walden the book, I know of no other comprehensive guide to the physical place. This remains puzzling to me, given that Walden Pond is a New England icon ranking with fieldstone walls, red lobsters, sugar maples, town greens, sandy beaches, and Fenway Park.  Perhaps it’s because the book of the place deeply shadows the place of the book.  Perhaps it’s because the droughty, pine-oak woodlands and acetic water are ecologically impoverished relative to the richer, muddier, riparian habitats of the nearby river valleys. Or perhaps it’s because it takes a geologist to see the textural details of the setting