Forever young: China's 'dancing aunties' kick up their heels

Two women from a square dancing team striking a pose for a photograph in a public park in Shanghai.

In a sparkling white cap and oversized sunglasses, 55-year-old retiree Zhang Yongli and dozens of neighbours liven up a Shanghai park by doing the jitterbug, part of a public dance craze that has become China's national pastime.

Every day, an estimated more than 100 million people - dubbed "dancing aunties" as they are primarily older women - take over squares and parks to tango, waltz, and grind out everything from flamenco to Chinese traditional dance.