The Harry Potter studio tour is about to get a “significant expansion” as Warner Bros has announced multi-million pound development plans for its studios in Hertfordshire, UK.

Following a 10-year masterplan submitted for planning application earlier this month, the Leavesden facility, which has filmed blockbusters including all eight Harry Potter movies, Goldeneye and Star Wars: The Phantom Menace, will increase its size by around a quarter.

Since opening to the public in 2012, the active movie studio-cum-visitor attraction has welcomed over five million visitors - more than Edinburgh castle, London Zoo or Stonehenge, according to the studios’ economic and social assessment report.

The studio tour has recently announced Halloween plans featuring the Dark Arts, running from October 16 through November 1, but has not yet commented what the expansion plans entail. The wizarding world also has a Christmas spectacular lined up between November 14 through to January 31, 2016.

The attraction’s most recent and significant investment came in March when it debuted its 20,000sq ft (1,858sq m) Platform 9 ¾ expansion, bringing the original Hogwarts Express back to its studio home for visitors to experience.