Cool things to do in summer

The daydream-inducing prospect of a long, hot summer, delicious as it may be, raises a serious question. What do you do in Beijing when the temperature is approaching 40 degrees, other than gaze wistfully out the window of your air-conditioned office, or maintain a sensible body temperature by way of ingesting a steady flow of cold beer at a Houhai bar? Get out of town of course, if you know what’s good for you.