I usually walk across a bridge that offers the possblility of witnessing a plane flying over a car that is driving over a train that is running over a boat. Although, of course, such a conjunction of transport options rarely occurs. Mostly there are just cars, pedestrians and bikes passing over skiffs and other varieties of sporting and pleasure craft. The occassional freight train does shunt along the track from time to time, but its haphazard timetable rarely seems to coincide with the desire of any canoeists to paddle beneath the elevated rails. I don't recall ever looking upwards and spotting a plane, probably because I am too busy staring downriver at the view of the city.