Japanese Emperor Naruhito visits the Thames Barrier during a UK state visit to strengthen ties with Britain.

Japanese Emperor Naruhito visits the River Thames's Thames Barrier during a UK state visit to strengthen ties with Britain. His fascination with the river began 40 years ago when he studied 18th-century commerce on the river as a graduate student at the University of Oxford. The visit highlights his continued interest in the waterway that is the heart of London.