When I was in high school, I was offered the opportunity to visit England with a group of classmates, staying for two weeks to live with a family there, attend school, and sight-see. It was a wonderful experience, and I long to go back again some day.
Now, when I think about traveling to the United Kingdom, I think about visiting London most of all. Of course, I would also want to take my children to visit Oxford and Cambridge, and to see some of the rural areas (we might need a couple of weeks to accomplish this!), but London is the first thing to come to mind.
Perhaps that's because one of my favorite memories from my high school trip is of being set free of our teachers and guides so that we could go shopping, have a nice meal in a London restaurant (we chose Beefeaters), and feel truly independent. We even ordered wine with our supper!
Check out the group of us, enjoying our visit (though we weren't in London in this pic):