Pure adventure

Every one has a kid inside... at least everybody SHOULD!
In my opinion this is one of the best adventure book ever written, it can be read in so many different ways that basically it never gets you bored and always leaves you something new to think about. I first read it when I was a kid, then it rested in my library for years and every now and then it just end up in my hands..
The taste of the first time I devoured this book still lingers everytime I go through its pages and the memories of adventure, of fantastic travels and of amazing discoveries brings me back to a warm and comfortable period, when everything was clean...

By the way, can you guess what book I'm talking about??? Should be quite easy also for not italian readers as some "key" words are plain to see...