Rooted in Zoroastrianism, an ancient monotheistic religion, Nowruz festivities are celebrated in countries with significant Persian cultural influence, including Iraq, Iran, Afghanistan, Turkey and Kazakhstan.

Historical accounts suggest that Nowruz celebrations occurred in ancient Persepolis during the Achaemenid Empire (550-330 B.C.). Mythology centered on its inception includes tales of a Persian king soaring across the skies in a jeweled chariot on the first day of spring.

Across regions, events during Nowruz, which translates to “new day” in English, vary according to customs, but they share common themes of rebirth, new beginnings and the celebration of nature.

“Nowruz has a lot of symbolism around renewal—renewal of nature, renewal of relationships,” Shadi Mokharti, a professor at American University in Washington, D.C., tells the School of International Service. “It is usually the highlight of the year for most Iranians.”

To symbolize the new year's fresh start, celebrants often engage in spring cleaning, or “khaneh tekani,” gift exchanges, family gatherings, buying new clothes and more. Children often enjoy a break from school during this time.

“All houses undergo a big cleaning,” Zohreh Mirsharif, a world languages and cultures professor at American University, adds. “People will change the colors of the walls; they will wash everything. This is the new beginning.”

One common pre-festival ritual involves leaping over fire and streams to cleanse the past year’s negativity. “Many households also replenish their water supplies on the last Wednesday of the year,” UNESCO notes.

Another notable Iranian tradition is the gathering of families around the ceremonial Half-Sin table, which displays seven items beginning with the Persian letter “sin,” each holding special symbolism. The table includes apples (seeb) for beauty, garlic (seer) for health, vinegar (serkeh) for patience, hyacinth (sonbol) for spring, sweet pudding (samanu) for fertility, sprouts (sabzeh) for rebirth and coins (sekeh) for wealth.

On the 13th day of Nowruz, some countries observe sizdah bedar, a custom that involves picnicking outside to ward off bad luck. “Since the 13th is an unlucky day, entire families go on picnics and take with them the sprouts (sabzeh) from the haftseen table,” NPR reports.

The sprouts, or sabzeh, is wheat, barley, lentil or other sprout grown in a pot. It’s believed that the sabzeh absorbs the previous year's pain and trouble and throwing it into water at the end of the festival symbolizes a letting go of those misfortunes with the new year.

In Afghanistan, a date-based dessert called haft mewa is served, and buzkashi, a polo-like sport played with a goat carcass as a ball, is played. In Uzbekistan and Turkmenistan, revelers share a sweet dish called sumalak from communal pots.

“What to Know About Nowruz, a 3,000-Year-Old Festival Celebrated by Millions Worldwide,” Time
“International Nowruz Day, 21 March,” United Nations
“Nowruz, A gathering of people with a common heritage along the Silk Roads,” UNESCO
“Nowruz: Persian New Year's Table Celebrates Spring Deliciously,” NPR
“Happy Nowruz! Five Facts About the Persian New Year,” American University