With two weeks to go before the start of Madrid's five-day Rock in Rio festival on June 4, the organization said it has sold 10% more tickets than at this stage before the city's first Rock in Rio in 2008.

Organizers expect the total audience to reach 320,000, up from 290,000 in 2008.

The figures were revealed May 18 by Roberta Medina, VP of Rock in Rio and daughter of the brand's Brazilian founder and current president, Roberto Medina. She was speaking to journalists at the official presentation of Rock in Rio Madrid at Rock City, the festival site at Arganda del Rey, 17 miles from Madrid.

Her father is in Lisbon in neighboring Portugal, where Rock in Rio Lisbon will be staged during the next two weekends. But two weeks ago, Roberto Medina told billboard.biz that after seven Rock in Rio festivals - it started in Rio de Janeiro, Brazil, 25 years ago and then headed to Lisbon and Madrid - the event will return to Brazil in 2011.

It will also "almost certainly" be held in Poland in July 2012, and negotiations have begun to hold a Rock in Rio in London, probably in 2012. A third Madrid festival is also planned for 2012.

"There is no other site like this in the world," Roberta Medina said on the main 98-meter wide and 28-meter high stage in Arganda's Rock City. "Some 8,000 people worked to build it in 2008 and improve it for this year, and its daily capacity is 100,000".

Roberto Medina said two weeks ago that Shakira's June 5 appearance on the same day as Rihanna, Calle 13 and David Guetta has sold most tickets, followed by Metallica and Motorhead on June 14, and Bon Jovi and John Mayer on June 4.

Miley Cyrus headlines Rock in Rio's first ever "family day" on June 6, together with Amy Macdonald and McFly. "At the first Rock in Rio Madrid, we were really impressed to see so many dads with their son or daughter sitting on their shoulders," said Roberta, "so we decided to have one day this year dedicated to children." She said every child entering the site that day would wear a bracelet with their name and parents' phone number.

Rage Against the Machine headline on June 11, together with Jane's Addiction and Cypress Hill. The reason the final day is being held on a Monday (June 14) is because Metallica could not play Rock in Rio on the preceding Saturday or Sunday.