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 prays at the edge of a river during a protest against the building of a pipeline near the Standing Rock Indian Reservation near Cannonball, North Dakota, U.S. November 2, 2016. (Photo by Stephanie Keith/Reuters)

A protester uses molotov cocktails against riot police during May Day protests on May 1, 2010 in Athens, Greece. (Photo by Milos Bicanski /Getty Images)

A man drinks at a "colored" water cooler in a streetcar terminal in Oklahoma City, July 1939. (Photo by Reuters/Library of Congress)

This photo provided by Steamboat Ski Resort shows hot air balloons that visitors can tour in above the town and mountains in Steamboat Springs, Colo. Wild West Adventures offer continental breakfast, champagne ceremony with flight certificates and courtesy pick-up are included. (Photo by Larry Pierce/AP Photo/Steamboat Ski Resort)

An artist has discovered a bizarre way to create his work – by coating the feet of insects with paint who then crawl across the canvas creating intricate pieces of art. (Photo by Caters News)

Boys play with water as they celebrate Myanmar's New Year Water Festival of Thingyan in Yangon, April 13, 2016. (Photo by Soe Zeya Tun/Reuters)

People stroll alongside one of the hills of the Tio Pio park in Madrid, Monday, January 25, 2016. The park is a high viewpoint frequented mostly by locals due to its view of the Spanish capital skyline. (Photo by Francisco Seco/AP Photo)