Witch Nose Island (known as Devil Nose Island until 1967) is the most secure prison on earth.
The entire perimeter is ringed by 27 krypto-web fences, 11 of which are electrified. The water around it is freezing and full of shnarks (which are more vicious than sharks), flesh-eating, saw-toothed doublodiles and killer electric rays. No prisoner has ever escaped from it.
Famous inmates include:
Name: Jerrold McMillan the Midnight Train-Thief
Prison number: WNI66912
Crime: Train robbery (he stole an entire train, including its passengers, so technically it was also a kidnapping)
Sentence: 25 years
Name: Teresa Nagg-ohorowitz
Prison number: WNI54871
Crime: Incessant nagging of her children
Sentence: 5 years
Name: Aloysius McDermottsonnsdottir
Prison number: WNI67329
Crime: General annoyingness
Sentence: 1 year
Name: Clementine Constantinius
Prison number: WNI44093
Crime: Saw-toothed Doublodile trafficking
Sentence: 10 years