Ticket prices are set to rise, while the main car parks for those heading to Llanddwyn beach on Anglesey could be closed off from mid-morning.
He surprised those attending the screening of the series when he walked into a central London hotel and sat with journalists to watch the first three episodes.Guardians will focus on how the work of rangers - who protect endangered animals - has become significantly more risky. Around 1,400 rangers have died in the past decade.
"This is now one of the most dangerous jobs on the planet," the prince told reporters."It shouldn't be. Protecting the natural world shouldn't be that dangerous."Being a soldier, a police officer, the emergency services - these jobs are dangerous, people put their lives on the line.
"I don't think people realise it's the same for these guys and girls around the world."He attributed the increased threat to "community conflicts or civil wars, or illegal fishing, or poaching - whatever it might be is just spreading further and further across the globe".
A friend said the prince turned up to emphasise the importance of the series to him on a personal level.
"The project was driven by him," the friend told the BBC. "He wanted to show the incredible work rangers do for people around the world."The festival, which is in its 18th year, started on Thursday and ends on Sunday evening with the Austen event.
Austen was a 19th-century novelist who continues to have huge appeal today. Her six novels have sold millions of copies and have been turned into TV shows, films and even musicals.Her portrait was chosen to appear on the £10 note in
, in a nod to her literary legacy.Stevenson played Augusta Elton in a 1996 film adaptation of Austen's Emma, which starred Gwyneth Paltrow in the title role, and she has also recorded unabridged audiobooks of all of Austen's novels.