<P> The technicians worked with New Zealand locals to get many of the sounds . They re-recorded sounds in abandoned tunnels for an echo - like effect in the Moria sequence . 20,000 New Zealand cricket fans provided the sound of the Uruk - hai army in The Two Towers, with Jackson acting as conductor during the innings break of a one - day international cricket match between England and New Zealand at Westpac Stadium . They spent time recording sounds in a graveyard at night, and also had construction workers drop stone blocks for the sounds of boulders firing and landing in The Return of the King . Mixing took place between August and November at "The Film Mix", before Jackson commissioned the building of a new studio in 2003 . The building, however, had not yet been fully completed when they started mixing for The Return of the King . </P> <P> The first film has around 540 effect shots, the second 799, and the third 1,488 (2,730 in total). The total increases to 3,420 with the extended editions . 260 visual effect artists began work on the series, and the number doubled by The Two Towers . The crew, led by Jim Rygiel and Randy Cook, worked long hours, often overnight, to produce special effects within a short space of time . Jackson's active imagination was a driving force . For example, several major shots of Helm's Deep were produced within the last six weeks of post-production of The Two Towers, and the same happened again within the last six weeks on The Return of the King . </P> <P> The trilogy's online promotional trailer was first released on 27 April 2000, and set a new record for download hits, registering 1.7 million hits in the first 24 hours of its release . The trailer used a selection from the soundtrack for Braveheart and The Shawshank Redemption among other cuts . In 2001, 24 minutes of footage from the series, primarily the Moria sequence, was shown at the Cannes Film Festival, and was very well received . The showing also included an area designed to look like Middle - earth . </P> <P> The Fellowship of the Ring was released 19 December 2001 . It grossed $47 million in its U.S. opening weekend and made around $871 million worldwide . A preview of The Two Towers was inserted just before the end credits near the end of the film's theatrical run . A promotional trailer was later released, containing music re-scored from the film Requiem for a Dream . The Two Towers was released 18 December 2002 . It grossed $62 million in its first U.S. weekend and out - grossed its predecessor with $926 million worldwide . The promotional trailer for The Return of the King was debuted exclusively before the New Line Cinema film Secondhand Lions on 23 September 2003 . Released 17 December 2003, its first U.S. weekend gross was $72 million, and became the second film (after Titanic) to gross over $1 billion worldwide . </P>

When did lord of the rings start filming