" The River Styx,' Annabeth murmured. 'It's so...'
'Polluted,' Charon said. 'For thousands of years, you humans have been throwing in everything as you come across - hopes, dreams, wishes that never came true. Irresponsible waste management, if you ask me. "

― Rick Riordan , The Lightning Thief (Percy Jackson and the Olympians, #1)