In Nikita's London, the cars drive on the right-hand side of the road. In reality, they drive on the left.
The cars in London all have European-style number/license plates; in reality, British vehicle registration plates look very different to those used in mainland Europe.
Nikita travels to London in this episode. Only the road markings are yellow in the show, when they should be white.
Although the chase and street fight is apparently in London, England, the traffic lights and road markings are clearly North American. With yellow traffic lights and yellow central road markings. In the UK center lines are white and traffic lights black.