Spring in Japan means cherry blossoms, and cherry blossoms means time for hanami (literally blossom viewing), which is an excuse for a picnic. All over the country this week, wherever there is enough open space below cherry trees, there will be groups of people seated on the seemingly obligatory blue plastic sheet eating either bentos (either home made packed lunches or ones bought in convenience stores) or having barbecues washed down with a beer or four. How much time is spent actually looking at the cherry blossoms is debatable, but it's a good excuse for a day out.
These pictures were taken at Tetsugakudo Park (philosopher's park, I think) in Nakano on a cloudy Saturday.