After the 6th century, the Circus fell into disuse and decay, and was quarried for building materials. The lower levels, ever prone to flooding, were gradually buried under waterlogged alluvial soil and accumulated debris, so that the original track is now buried 6 meters beneath the modern surface. In the 11th century, the Circus was "replaced by dwellings rented out by the congregation of Saint-Guy." In the 12th century, a watercourse was dug there to drain the soil, and by the 16th century the area was used as a market garden. Many of the Circus's standing structures survived these changes; in 1587, two obelisks were removed from the central barrier by Pope Sixtus V, and one of these was re-sited at the Piazza del Popolo. In 1852 a gas works was built on the site by the Anglo-Italian Gas Society. It remained in situ until 1910 when it was relocated to the edge of Rome. Mid 19th century workings at the circus site uncovered the lower parts of a seating tier and outer portico. Since then, a series of excavations has exposed further sections of the seating, curved turn and central barrier but further exploration has been limited by the scale, depth and waterlogging of the site. The Circus site now functions as a large park area, in the centre of the city. It is often used for concerts and meetings. The Rome concert of Live 8 (July 2, 2005) was held there. The English band Genesis performed a concert before an estimated audience of 500,000 people in 2007 (this was filmed and released as When in Rome 2007). The Rolling Stones played there in front of 71,527 people on June 22, 2014 for the Italian date of their 14 On Fire tour. The Circus has also hosted victory celebrations, following the Italian World Cup 2006 victory and the A.S. Roma Serie A victory in 1983 and 2001. In May 2019, a new virtual/augmented reality experience, the "Circo Maximo Experience", opened on the site, taking visitors on a journey through the site and its history.  (https://www.youtube.com/watch?v=t8Thra4T80c)- AP Archive. Video of celebrations after Italy won the 2006 World Cup Finals in Germany. http://www.aparchive.com/metadata/youtube/c195a43af063a416da53a7ec15430ef2.