" Caves are cool in warm weather. Beware of bats, however. Bat urine will give you, as well as animals such as dogs, the rabies. Photograph supposedly shows an early man drawing on the walls of a cave. Such cave drawings are nearly all faked but are great tourist attractions. Cave drawings are invariably "discovered" in remote parts of a cave. If they were allegedly found in readily accessible areas of caves, they would be quickly declared to be fakes. "

― , How to Get out of the Rat Race and Live on $10 a Month