One major difference is the size of the cars, well really the size of everything in general. With a population 20% of America on 2.5% of the land, things are definitely not as roomy. Most people here drive hatchbacks, coupes, or sedans (saloon cars). While these cars are smaller many are just as nice. It seems like there are many more Audi’s, Mercedes, and of course BMWs & Mini’s (even some Aston Martins and Bentley’s). The trend is mostly driven by the tight parking spaces and narrow roads, but also by the green movement. Hummer Bait Smart Car anyone? No? Didn’t think so.
If you want to drive in England (or any other country) make sure your insurance still covers you. If it doesn’t and you want to drive a rental car you’ll need to get insurance from the rental place. Though you have to be 23-25 years old minimum at most places.