'Impossible to forget': Loved and feared 5m saltie 'Trevor' found dead

One of the Northern Territory's most loved and feared personalities, a five-metre saltwater crocodile named Trevor, has died.

The giant crocodile was found dead in the Adelaide River, likely as a result of being struck by boat propellers, a spokesperson from the Department of Tourism confirmed.

Believed to be more than 60 years old, Trevor was renowned by locals and tourists alike for his fearsome size and nature.

"He was an impossible croc to forget," Spectacular Jumping Crocodile Cruise skipper Alex Williams said.

"Not just big, but very stubborn and hands down the most aggressive crocodile we have down here.

"The first time I saw him jumping and flying out of the water I was completely dumbstruck."

Mr Williams said he's worked with plenty of crocodiles but seeing Trevor jump "never got less cool".

"Trevor tended to be a crocodile that most people either loved or hated. But most people loved him.

"If you were outside the boat he wouldn't hesitate to take you out. But we still love them. We just know the limits we have with them."