Because Frankfurt is more-or-less in the center of Europe a great many [cheap] flights drop you off there. Unfortunately, it is not-beautiful industrial town. It does host a number of conventions (that central location card) of which the annual International Book Fair is the only one really worth attending. Although I was in the book business for years, I never did make it to the Book Fair. But I was stuck in Frankfurt for two days, waiting to connect with a friend arriving on another cheap flight from a different point of origin. Since there was nothing else to do, I went to the zoo. It was a good zoo, not great and by today’s standards probably not ecologically correct. But it had an excellent baboon island. I spent four hours watching those baboons and when I had to leave, I realized that, even if I never travelled anywhere ever again, I had seen all there was to see in human behavior.