“One day, I went to the Kovilj Monastery and experienced a great temblor inside my soul the moment I heard monks chanting.

Pursuing his dream further, he founded the group Balkanopolis, with whom he held many concerts and published an independent album titled Let Iznad Balkana (One Flew Over the Balkans).

In addition to his talent for playing, Slobodan Trkulja also has impressive singing abilities, which he developed by listening to traditional Serbian throat-singers.

On September 15, the same year, he participated in a charity concert of ethnic music "Kuća na putu” (“House on the road”) in Belgrade's Sava Center, with blessings of the Serbian Patriarch Pavle.

In December, same year – same place, with Belgrade Philharmonic Orchestra and “Balkanopolis”, Trkulja held a groundbreaking concert, conducted by Arjan Tien, called Prizivanje kiše (Invocation of rain) where he singlehandedly introduced Serbian traditional instruments to contemporary music.

This concert was held on the occasion of the completion of the Dutch presidency of the European Union organized by the Netherlands Embassy in Belgrade.

On April 17, in Hilversum, Netherlands, Balkanopolis and Metropole Orchestra started their collaboration by recording the program for the interval act of Eurovision.

On their debut album, "Prizivanje Kiše" ("Invocation of Rain", published in 2006 by PGP RTS), Trkulja build a fusion of modern jazz and original folklore.

After this, he easily made his way through the Latin jazz scene, traveling through Benelux with the Latino big band of Eddie Martinez from Colombia.

At the Concertgebouw in Amsterdam, in a traditional New Year’s concert, January 2002, he performed his Pythagora Oro, together with Dutch Brass Ensemble.

The performance at this concert (which was directly transmitted by the Dutch television) was the high point of Trkulja’s career, which gained him admiring reviews and earned him recognition in the Netherlands.

On 6 February 2005 he won the Dutch Erasmus Prize for performing jazz saxophone and clarinet pieces for 45 minutes with drummer Arie Den Boer as his only accompaniment.

Other than a sum of money from Rotterdam Conservatory,[10] the prize included a number of concerts at the renowned jazz clubs in the Netherlands.

Special guests were fado diva Mariza, soul singer/composer Oleta Adams, Lebanese young star Mayssa Karaa and renown singer from Senegal Baaba Maal.

In front of the 10.000 people in the audience, Balkanopolis was the first neo-traditional group to perform their own concert in a venue of that scale, marking their 18th birthday.

On Beovizija 2007 Slobodan Trkulja and “Balkanopolis” competed with his composition ”Nebo” (“Sky”), which combines traditional and Byzantine ecclesiastical chant.