<P> Also in 2000, the then unknown British actors Emma Watson and Rupert Grint were selected from thousands of auditioning children to play the roles of Hermione Granger and Ron Weasley, respectively . Their only previous acting experience was in school plays . Grint was eleven years old and Watson ten at the time they were cast . </P> <P> Los Angeles Times writer Geoff Boucher, who conducted the above - mentioned interview with Heyman, added that the casting of the three major roles "is especially impressive in hindsight . The trio's selection was arguably one of the best show - business decisions over the past decade...they have shown admirable grace and steadiness in the face of teen superstardom ." </P> <P> Filming of the series began at Leavesden Studios, Hertfordshire, England, in September 2000 and ended in December 2010, with post-production on the final film lasting until summer 2011 . Leavesden Studios was the main base for filming Harry Potter, and it opened to the public as a studio tour in 2012 (renamed as Warner Bros. Studios, Leavesden). </P> <Table> <Tr> <Th> Motion Picture </Th> <Th> Director </Th> <Th> Writer </Th> <Th> Producer (s) </Th> <Th> Composer </Th> <Th> Novel by J.K. Rowling </Th> </Tr> <Tr> <Td> Harry Potter and the Philosopher's Stone </Td> <Td> Chris Columbus </Td> <Td> Steve Kloves </Td> <Td> David Heyman </Td> <Td> John Williams </Td> <Td> Harry Potter and the Philosopher's Stone </Td> </Tr> <Tr> <Td> Harry Potter and the Chamber of Secrets </Td> <Td> Harry Potter and the Chamber of Secrets </Td> </Tr> <Tr> <Td> Harry Potter and the Prisoner of Azkaban </Td> <Td> Alfonso Cuarón </Td> <Td> Chris Columbus, David Heyman & Mark Radcliffe </Td> <Td> Harry Potter and the Prisoner of Azkaban </Td> </Tr> <Tr> <Td> Harry Potter and the Goblet of Fire </Td> <Td> Mike Newell </Td> <Td> David Heyman </Td> <Td> Patrick Doyle </Td> <Td> Harry Potter and the Goblet of Fire </Td> </Tr> <Tr> <Td> Harry Potter and the Order of the Phoenix </Td> <Td> David Yates </Td> <Td> Michael Goldenberg </Td> <Td> David Heyman & David Barron </Td> <Td> Nicholas Hooper </Td> <Td> Harry Potter and the Order of the Phoenix </Td> </Tr> <Tr> <Td> Harry Potter and the Half - Blood Prince </Td> <Td> Steve Kloves </Td> <Td> Harry Potter and the Half - Blood Prince </Td> </Tr> <Tr> <Td> Harry Potter and the Deathly Hallows--Part 1 </Td> <Td> David Heyman, David Barron & J.K. Rowling </Td> <Td> Alexandre Desplat </Td> <Td> Harry Potter and the Deathly Hallows </Td> </Tr> <Tr> <Td> Harry Potter and the Deathly Hallows--Part 2 </Td> </Tr> </Table>

When did they start filming the first harry potter movie