Piccadilly Circus is actually not a circus, but a plaza. There are lots of streets in Picadilly Circus where you can shop, watch a show, and eat.
London Eye
The London Eye is also one of the many attractions in London. However, the waiting time is usually long, so you might need a bit of patience for queueing.
Big Ben
Big Ben is located in London, the capital of the United Kingdom. It can be found on the north end of Westminster Palace, which is the home of the British Parliament.
British Museum
Most of the museums in UK are free of entry, including the British Museum. The British Museum is really massive, it might even take you a day to explore and see around.