Hyde Park, with its benign chaos of walkers, strollers, skaters doing fancy footwork round lines of cups, and tourists trying in vain to head for Buckingham Palace, is always fun to cycle round.
And the Serpentine Gallery is always enjoyable to visit, with its free exhibitions (the current one being a random-feeling selection of works and photos from Wolfgang Tillmans, until 19 September).
But there's a curio we've not seen before in the Pavilion, a cafe-bar and ping-pong venue flooded with blood-red light that's open until 17 October. The seats by the bar are like saddles, and the footrests are like pedals. You can spin them round as you sip your only slightly overpricey beer or cappuccino. You can tell the pav was designed by a Frenchman.