One of the first things an American traveler in Great Britain notices is all the very small cars! In our neighborhood at home, the prototypical vehicle is some variety of SUV. But the cars one immediately notices after landing at Heathrow are little ones, designed for basic transportation.
The one shown here isn't the littlest; actually, it (as a four-door) is probably among the largest of the smaller style cars. The really little ones hold only two people in what looks to be a rolling acorn.
In the US, the argument would be that such a car is "too dangerous" to drive in heavy traffic. But apparently in the crowded streets of London, many people find such smaller vehicles to be perfect, or, as they would be more likely to say, "brilliant."
Although, to be fair, no car is truly "brilliant" there. On the whole it is better for most to ride the fine mass transportation (the tube or buses), to use a taxi, or to bicycle--or to walk.
But, still, noticing little cars (along with seeing the sign for the underground) was our very first impression of a somewhat different, but somewhat similar, culture. Where people speak the same language that Americans do, write with the same words and letters, but also have what is at least in part a rather different take on dealing with the problems of 21st century life.
A good place to observe differences, try to learn from them--but also with the necessity of "minding the gap."