In 1998, Tiësto joined forces with fellow Dutch deejay Ferry Corsten to create the trance based duo of Gouryella. The first Gouryella track, also called Gouryella, was released in May 1999 and became a huge hit scoring various chart positions around the world, including a top fifteen position in the UK Singles Chart. Tiësto showcased this track in Magik Three: Far from Earth as well as in his set at the first ID&T Innercity party (Live at Innercity: Amsterdam RAI), his first major breakthrough. The next single, entitled "Walhalla", also made it on the charts worldwide, peaking at No. 27 in the UK Singles Chart. Released via Ferry's Tsunami, both singles went on to be certified Gold on record sales. During these years, Tiësto also collaborated with Benno de Goeij of Rank 1 under the name Kamaya Painters. In November 1999, he released the first installment of the In Search of Sunrise series. Since then, he performed monthly as a resident at Gatecrasher in Sheffield, and played a 12-hour set, his longest, in Amsterdam. On December 31, 1999, he performed at Trance Energy 2000, a special party held by ID&T for the turn of the millennium.