Turkey's entertainment culture spans millennia and operates across formats that few other countries can match. The Istanbul Music Festival in June stages international classical music in historic venues including the Hagia Eirene Byzantine church, where the acoustics and the setting together produce an experience of unusual atmospheric power. The Aspendos International Opera and Ballet Festival performs in a 2nd-century Roman theatre in remarkable condition, in a format that draws on the building's original function in the most direct way possible. The Istanbul Jazz Festival, the Istanbul Film Festival, and the Istanbul Biennial anchor the contemporary cultural calendar. Turkish classical music, rooted in the makam modal system; arabesk popular music; and the sema ceremony of the Mevlevi Order — the whirling dervish ritual of Rumi's Sufi order, performed at specific tekke lodges — each represent entertainment traditions of deep cultural specificity.