Emperor Naruhito and Empress Masako are on the third day of their official state visit to the UK.

The Emperor visited the Thames Barrier, one of the largest moveable flood barriers in the world.

Usui Masako, NTV Commentator: The Emperor, whose life's work is the study of water issues, visited facilities to protect the city from water disasters here on the River Thames.

During his studies at Merton College in Oxford, the Emperor’s research theme was the 'history of water transport on the River Thames'.

In relation to water issues, he has visited facilities around the world and was keen to visit the Thames Barrier during this visit.

The Empress, on the other hand, is believed to be spending some time in the hotel, as she is a little tired from her long journey.

Emperor Naruhito and Empress Masako are on an eight-day official visit to the UK as state guests.

The Emperor and Empress smiled warmly and waved to those who had come out to greet them.

On the second day of their official visit, Emperor Naruhito visited Japan House London, which promotes the appeal of Japanese culture.

Emperor Naruhito: So many things!

He was impressed by the wide range of items on display, including Wajima lacquerware from Ishikawa Prefecture, Japanese candles, and many other items.

Emperor Naruhito: Having both spent time studying there, the UK holds fond memories for each of us, so we are looking forward to this visit.

The Emperor attended Merton College in Oxford from 1983 until 1986 to conduct postgraduate research on the history of transportation on the Thames.

During his time in the UK, he could be seen riding bicycles through the streets or shopping in various stores.

In fact, the clothing shop where he shopped over 35 years ago is still open in Oxford, and by coincidence, the Empress had also visited it.

Shop Assistant: We didn’t realize who she was before, but later I found out it was Masako, and everyone in the shop was talking about how beautiful and elegant she was.

Three years after Emperor Naruhito has returned to Japan, Empress Masako went to study at Balliol College in Oxford for two years.

The Emperor was also known to frequent pubs during his time studying abroad.

Roger Bacon, former security for Emperor Naruhito: The Emperor could act like any other student here in the UK, by doing things like going shopping or even visiting a pub.

There was even a time when Emperor Naruhito was refused entry to a nightclub because he was wearing jeans.

Roger Bacon, former security for Emperor Naruhito: I have no doubt about this at all, but his time here in the UK must have reinforced his desire to enter more openly into Japanese society.

In his book “The Thames and I - a Memoir of Two Years at Oxford”, the Emperor described his mixed feelings about leaving the UK.

When I visit Oxford again, I will not be able to look around as a free student as I do now. The town itself will probably remain the same, but it will be my position that will change, and I feel a strange sense of frustration. I hope that in the not-too-distant future I will be able to visit the UK again with Masako, who also studied at Oxford University.

Following his visit to the Thames Barrier, Emperor Naruhito attended a reception organized by Japan-UK friendship groups in London.