Sardinia is home to one of the oldest forms of vocal polyphony, generally known as cantu a tenore. In 2005, Unesco classed the "cantu a tenore" among intangible world heritage. Several famous musicians have found it irresistible, including Frank Zappa, Ornette Coleman, and Peter Gabriel. The latter travelled to the town of Bitti in the central mountainous region and recorded the now world-famous Tenores di Bitti CD on his Real World label. The guttural sounds produced in this form make a remarkable sound, similar to Tuvan throat singing. Another polyphonic style of singing, more like the Corsican "paghjella" and liturgic in nature, is found in Sardinia and is known as "cantu a cuncordu".