Group Exercise in Public Parks Around the World

City parks do some of their best work before the office day starts. This gallery follows people who exercise together in public, from tai chi under the old trees of Beijing's Temple of Heaven to a free Saturday 5K in a London park and mass aerobics in central Bangkok. Every practice shown is low-impact or easy to scale, costs little or nothing, and welcomes anyone willing to stand at the back and copy the person in front. Most of these sessions happen around dawn; a few, such as Bangkok's aerobics and Hong Kong's Sunday kung fu shows, run later in the day, so check the hour before you set an alarm. Yoga and outdoor gym machines are left out to keep the focus on group practices you can join with nothing but comfortable shoes.