Detective Comics #526

Giant-sized issue commemorating Batman's 500th appearance in DETECTIVE COMICS! Featuring the first appearance of Jason Todd as Robin! Batman teams with Robin and Batgirl to take on twenty of his deadliest foes, including the Joker, Catwoman, Killer Croc, Mister Freeze, Penguin, and more!

All My Enemies Against Me! -- 2. A Special 500th Anniversary Bonus Pin-up by Bob Kane.
This issue marks the 500th appearance of Batman in Detective Comics