You might be onto something there! Around where I live, there a quite a few places that would be quicker to reach by riding a horse up the bridleways instead of driving. One of the biggest problems is that, in the older parts of the villages, there's also nowhere for people to park their cars - everywhere you go, cars are parked up on the pavements so that other drivers can get past, and pedestrians end up having to walk in the road; it only takes one person to stop to pick up a passenger, or meet a pedestrian in the middle of the road, and the whole road is blocked. Some of the schools even have a PCSO outside every day to direct people so that it doesn't just become a chaotic free-for-all of drivers arguing about who lets who through.
Like you say, they never take this into account when they build another few hundred new houses. I understand the need for the homes, and they're mostly just where old mill buildings used to be, but the traffic into town sometimes becomes one big, long queue from the town centre out to villages three or four miles away. Of course, even people who could take the bus still don't, because they'd rather be in their cosy car with their favourite music than stuck in the queue on the bus; and then the bus services get cut back! When drivers moan to me about the traffic, I always like to remind them; "but you are traffic!".
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