Picnicking under cherry blossom (Prunus sp.) trees in Ueno, Tokyo's oldest and biggest park. A man (bottom right) can be seen wearing a face mask. Face masks are most often used in Japan by people who have colds, so as not to infect others, or to avoid catching infections themselves. This park was opened to the public in 1873 and has numerous temples, shrines, unparalleled art museums and a zoo. Photographed in the spring, when cherry blossom viewing parties (hanami) take place, at Ueno Park, Tokyo, Japan.