Emma Watson didn't realise she was famous until she went to study at college in America.

The actress became recognisable across the world playing witch Hermione Granger in the 'Harry Potter' movies but she claims she wasn't aware of her star status until enrolled at Brown University in Rhode Island, Massachusetts, in 2009 to study English literature.

Emma quickly realised her presence was a big deal to her fellow students and she was followed by paparazzi most days.

Speaking in the new issue of Teen Vogue, she said: ''It sounds stupid, or completely unbelievable, but that was when I really realised that I was famous.''

Emma, 23, believes she was unaware of her fame because she lived in a bubble when she was shooting the wizard franchise with Daniel Radcliffe and Rupert Grint.

Speaking about her 10-year stint in the films, she said: ''I think, in a way, I was very protected during 'Harry Potter' because I was working all the time. I would get in the car, go to the studio, and go home.

''There are still days when I deal with [fame] horribly and there are days when I deal with it really well.''

The 'Bling Ring' star strikes a pose on the cover of the popular teen magazine and she seems to be very pleased with her appearance in the publication.

She wrote on Twitter: ''Just seen my new teen vogue cover! its awesommmeeee. I have a quiff! I think ill be 50 and begging to be on the cover of teen vogue. :) (sic)''