Down here or up there? South of Banbury we meandered under the M40 at a steady 3mph -- which was rather faster than the stationary Friday afternoon traffic up there.
M40 traffic noise blights a long corridor of Oxfordshire - we went for a walk in the evening and you can hear it echoing for miles.
The noise is almost entirely road noise rather than vehicle exhaust noise. If someone could only invent a quieter road surface this part of the world would be a much more peaceful place.