With summer's heat punching in early this year, I'm already angling for riverside relief. I trundle down to Ota Ward's Rokugodote, the southernmost train station in Tokyo's 23 wards, and a stone's throw from the Tamagawa (Tama River). The 138-km-long Tamagawa, which in this location divides Tokyo from Kawasaki, is bound to have some chill spots, I think.

Leaving the station and turning southward, I find and scale a high levee, to survey not the river but a floodplain full of baseball fields. Nineteen, in fact. The Tamagawa Yakyujyo, I learn from a passerby, costs ¥3,000 to reserve a field for two hours of play on weekends, but only half that on weekdays. Despite the low fees, the fields are empty and eerily quiet midweek. Perhaps the noontime sun is simply too hot, or — here's a notion — everyone's busy working?

A ginger cat saunters up and brushes my leg, yowling conversationally. Offered a morsel of food, he licks it politely but has no appetite. As he stalks off through the grass and wildflowers, turning to call to me every few paces like a character from a Hayao Miyazaki film, I head off in the opposite direction, toward the river.