The Hulk was originally gray, not green.
The Hulk first appeared in his debut comic called “The Incredible Hulk,” released in May 1962.
The Hulk was created due to exposure to gamma radiation.
The Hulk has lots of long-forgotten superpowers one of which is being able to see ghosts!
The Hulk can breathe underwater
There are no diseases that make the Hulk sick. That's because the antibodies in his blood are so powerful
A blood transfusion from the Hulk led to the creation of a She-Hulk.
The Hulk was a founding member of The Avengers.