Some roads are part of our history. One often thinks of Route 66, immortalized in that wonderful rock track, or the A13, from Billy Bragg's parody of said rock track. Some roads, however, will never go down in history, or if they do it won't be for the right reasons. One such road is the M4. It's quite a big road as far as the UK's concerned, stretching some 200 or so miles west from London until it gets lost somewhere in south Wales.
Like most motorways, the M4 has all the usual amenities: a few well placed service stations1, nice stripes to separate the lanes, and the odd sign that usually says something helpful like "Huge delays: don't even think you're going to get where you want to go today".
The problem is that it's so mind-bendingly dull. It's a very straight road that goes through the flattest, dullest, most boring parts of England. Eventually, you do get to the Severn Bridge and the rather more interesting countryside of Wales, but as the motorway then decides to become only two lanes for most of its remainder (and therefore technically a dual carriageway) I don't think that really counts. (And also, I would prefer to think of Wales unspoiled by large gray scars in its beautiful landscape.) Also, if you're driving from London to Wales in the evening and returning in the morning you'll have the added joy of staring into the sun for five hours due to the east-west orientation of the motorway.
Another problem is that all the very worst drivers in the world perpetually drive backwards and forwards along the M4. The most common misconception these people seem to have is that this particular motorway has slow, cruise, and fast lanes. Most people choose "cruise" and then sit in the middle lane for the rest of their journey with empty spaces to their left and right.
So to sum up: ignore the M4. If you really have to travel from London to Bath, Bristol, Cardiff, or (God help you) Swindon, then take the train. The train service along this route is actually one of the few in the UK that is reasonably fast and efficient (that is, unless one carriage of your train catches fire at Swindon, which has, rather worryingly, happened to me twice). And if you must use the M4, for God's sake don't just sit in the middle lane.