Hiking through the Amazon rainforest gets a 10 on our tough-o-meter scale. Even with modern technology like Jeeps, tents that are nice than our apartment and GPS, we wouldn't want to brave the bugs, snakes, and wary tribesman with spears. Doing the same trip in Fawcett's time is off the charts on the tough-o-meter. Dude didn't even have DEET.
On the other hand, David Grann retells Fawcett's journey with easy-to-follow language. And although Grann weaves historical events and figures into his narrative, his writing style is more Dan Brown than history textbook. Reading The Lost City of Z is a breeze, especially if you can do it in front of a nice AC vent and as far away from nature as possible.
Sure, nature is nice in theory, but Lost City of Z reminds us that what nature really wants to do is kill you.