In the 1970s and 80s a deadly cocktail of toxic factory fumes and car pollution turned Mexico City into the world’s most polluted city. In response, the authorities came up with an ambitious solution: curb the use of each of the city’s two million cars for one day a week, the first time any country had tried such a bold plan. Ramon Ojeda Mestre is an environmentalist who was behind the initiative, introduced in November 1989. He tells Mike Lanchin about overcoming fierce opposition to the plan, and how some critics even predicted riots from irate motorists.

(Photo credit: Alamy)