The Sonisphere cinecast from the Sofia, Bulgaria leg of the touring rock festival was seen by more than 100,000 fans, according to promoter Stuart Galbraith.

The global June 22 cinecast featured the 'Big Four' of metal - Metallica, Slayer, Megadeth and Anthrax - and was beamed via satellite in HD to cinemas. It was distributed globally into hundreds of cinemas by New York-based BY Experience.

In the U.K. it was screened in 79 cinemas. "At the Odeon in Leicester Square in London there was a mosh pit, and at the end of the show they had a stage invasion, which is just phenomenal to even think about," says Galbraith. "Not only are we hitting the territories that we're playing with this tour, [with the cinecast] we've taken the Big Four and Sonisphere into countries we haven't been able to get to this year."

A DVD of the cinema presentation is set to be released later this year. TV deals have also been struck for sets from Sonisphere and in Britain ITV2 will screen highlights from the U.K. festival. VH1 will show Sonisphere in the U.S.

While the Big Four did impressive numbers in cinemas globally, the Sonisphere festival launched this year with close to 100,000 tickets sold for just one event at Bemowow Airport in Warsaw, Poland on June 16. It was the first time the four metal bands had shared a concert bill.

"That was quite incredible, the first time into the market," says Galbraith. "To have those four bands all on the same bill for the first time ever was a very special moment."

Sonisphere has also called at Jonschwil in Switzerland, Prague, Sofia and Athens. It is now in Bucharest and Istanbul (both June 25-27) and then travels to Madrid (July 9-10), Stockholm (Aug. 7) and Pori in Finland (Aug. 7-8). It wraps up with two nights at the 50,000-capacity Knebworth (July 30-Aug. 1). Rammstein and Iron Maiden headline with Anthrax, Pendulum, Alice In Chains, Alice Cooper, Motley Crue and Slayer also on the bill.

Iron Maiden will be playing three Sonisphere dates in August on the eve of the Aug. 15 release of their new album, "The Final Frontier" (EMI).

"It's a great launch for them for their album, in the U.K., Sweden and Finland," says Galbraith. It will be Maiden's only shows in those territories in 2010.

At Knebworth, Rammstein play their first ever outdoor show in the U.K. Metallica played all dates last year but it will not be appearing at Knebworth or Madrid in 2010.

Overall, almost 600,000 tickets have been sold for 19 days of Sonisphere at 11 sites in 2010, compared to 290,000 for seven days at six locations last year. Tickets in eastern and southern Europe tend to sell nearer the date than in western counties.

The World Cup has not proved a distraction either. While some other festivals showed games on big screens, Sonisphere has taken a defiant stand. "We've ignored it," says Galbraith. "Most self-respecting rock fans aren't into football."

Galbraith is already talking to potential headliners and sponsors for 2011, and expects to return to the U.K., Sweden and Finland, among others. He hopes for 12 to 14 Sonisphere festivals in 2011.

Sonisphere was launched in 2009 by Galbraith, series producer and director and CEO of Kilimanjaro Live, and John Jackson, festival creator and director and Metallica's booking agent at K2 since 1985. AEG, which backs Kilimanjaro, is also supporting the festival.