The tattoo's chief executive and producer, Brigadier David Allfrey, expects the Tattoo will again be a sell-out with almost 90 percent of the 220,000 tickets already taken up for the show, staged at the castle built on a volcanic core towering over central Edinburgh from August 3 to 25. The tattoo was first held in 1950, to an audience of 8,000.

"The theme this year is 'to make a diamond' and that really allows us to pick up on the diamond jubilee and allows us to talk about Queen Elizabeth's reign in the round," he told Reuters.

It also celebrates the huge changes that have taken place over the past 60 years, which Allfrey compared to the eras of previous queens, Victoria and Elizabeth I.

Asked about security, with the Edinburgh festivals running in parallel with the Olympic Games in London, police Chief Inspector Gavin Phillip told Reuters: "There's always a risk, but there is nothing specific this year. We monitor it on a daily basis, possibly more so on this year of the Olympics."

Music is an integral part of the tattoo, and this year's event will include 12 bands for the massed pipes and drums, ranging from Melbourne's "Rats of Tobruk" and the Australian Federal Police Band, South Africa's Cape Town Highlanders, the Canadian Army band and the British Army.

Also on show will be the band of U.S. naval forces in Europe flying in from Naples, and the "Top Secret Corps" making up Switzerland's foremost percussion group.

Setting the scene will be ancient Pictish warriors emerging from the soaring castle walls, with one picking up a shiny 'diamond' pebble from the esplanade in acknowledgement of the fortress's volcanic past.

A blast from a Bronze Age carynx horn will summon the massed pipes and drums to set the spectacle in motion.

Dance, popular music and comic book characters are all part of the show, with the King of Norway's guard making a ninth appearance at the tattoo with its display of precision drill.

The climax to the 90-minute show will be an orchestral re-enactment of the queen's coronation in 1953, the year after she succeeded her father George VI to the throne.

"A towering cathedral forms the backdrop and projected images, church bells and voice-overs vividly recall that momentous event," Allfrey said, with a grand musical finale and the James Bond tune "Diamonds are forever" as fireworks light up the night sky. (Editing by Paul Casciato)

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