Nowruz is Zoroastrian in origin and has comfortably outlived its origin. It falls at the vernal equinox, is preceded by a thorough cleaning of the house, khaneh-tekani, and by Chaharshanbe Suri, the fire-jumping on the last Wednesday eve, and is centred on the haft-sin table with seven symbolic items whose names begin with the letter s in Persian. Visits are made in strict order of seniority; the period ends on the thirteenth day with Sizdah Bedar, when everyone goes outdoors. It is now observed by some three hundred million people across Iran, Afghanistan, Central Asia, the Caucasus, Turkey, Iraqi Kurdistan and the Balkans, the overwhelming majority of them Muslim, and UNESCO inscribed it in 2009 with the UN recognising 21 March as International Nowruz Day. Attempts by clerical authorities in Iran after 1979 to downgrade it in favour of Islamic festivals were unsuccessful to the point of embarrassment. It is the largest surviving Zoroastrian contribution to world practice, and most of the people keeping it do not know that is what it is.