A Cambodian resident wearing a mask attends a ceremony at Pring Ka-Ek village on the outskirts of Phnom Penh, Cambodia, 09 June 2016. Villagers organized a ceremony to continue their local traditions by paying respect to the Neakta Pring Ka-Ek (Spirit house) to prevent them from diseases and to achieve abundant rice harvests and other agricultural yields. (Photo by Mak Remissa/EPA)

A period of relative stability has put the Iranian capital No1 on the list of world cities that have achieved biggest improvements in liveability over the past five years, as calculated by the Economist Intelligence Unit. The “most improved” top 10 contains some unexpected names. So, eg, the fourth place: Abidjan, Ivory Coast. Latest ranking: 128; Ranking five years ago: 131; Five-year index movement: 3.8%. Here: A supporter of Ivory Coast president Alassane Ouattara campaigns in a market in the city’s Koumassi quarter. (Photo by Sia Kambou/AFP Photo)

A woman stumbes as people run down Oxford Street, London, Britain, November 24, 2017. Police are responding to reports of an incident at London's Oxford Circus Tube station and have urged the public to avoid the area. (Photo by Peter Nicholls/Reuters)

Members of the SubCielo company perform during the fifth annual Puerto Rico Circo Fest in San Juan, Puerto Rico, Saturday, March 10, 2018. The festival is held simultaneously in several spots on the streets of the Old San Juan city on March 10–11. (Photo by Ricardo Arduengo/AFP Photo)

A model rehearses with a fabric face mask on, designed by Zhou Li for her Autumn/Winter 2020 collection show, during China Fashion Week in Beijing, following the novel coronavirus disease (COVID-19) outbreak, China on May 3, 2020. (Photo by Tingshu Wang/Reuters)

Members of the Israeli Mermaids Community bathe in the sea with a mermaid tails at the beachfront in Bat Yam, near Tel Aviv, Israel, Saturday, May 23, 2020. Members of the Israeli mermaid community gathered at the beachfront to mark the beginning of the bathing season. (Photo by Oded Balilty/AP Photo)

This photo taken on March 3, 2020 shows a tattooed Chin ethnic woman smoking at her house decorated with animal skulls in a village of Chin State, western Myanmar. (Photo by Sai Aung Main/AFP Photo)

Visitors take photos of the fluorescent sea in the waters of Paishi Village, Dalian City, Liaoning Province, China, May 24, 2020, from the night of May 24 to the early morning of May 25, 2020. The fluorescent sea in dalian is caused by noctilucent algae in the sea water. (Photo by Costfoto/Barcroft Media via Getty Images)