You can find the blue marlin in the offshore waters along all 3 U.S. coasts. The blue marlin is what most offshore fishermen consider to be the top prize of the ocean. Most blue marlin are found beyond the 100 foot fathom line. You will not find them around the inshore waters. They like to congregate near temperature breaks near lots of forage. They are very big and they provide an outstanding show once they are hooked.