This is the first book I ever mail ordered, back in 1980. I was in the sixth grade and beyond excited when this bulky thing showed up at our door. If you're interested in geography or some of the more iconic (and obscure) natural landmarks out there worldwide, places you've never imagined or ever heard of -- be they weird rock formations, underground rivers/caverns, chasms, rivers, canyons, holes in the ground, any idiosyncratic geological oddity -- then this book is a must have; an excellent introduction to the natural wonders of the world. ( )