The large number of these rattlesnakes are kept on display in the huge concrete pit where they may be viewed closely but safely. Diamond-Back Rattlesnake is the largest, most dangerous of America snakes. Feeds on mammals. Prey killed with venom. Thorne born alive in litters of 10 to 30, are poisonous birth. Gets 2 or 3 rattles a year. Maximum striking distance about 2/3 their own length. Venin used in making Anti-Vein.