The Queen unveils a plaque to open Bush House

The transcript details a ceremonial event at King's College London, where a plaque is unveiled by the Majesty to formally open the institution at Busch hubs. A small gift is presented to the Majesty, symbolizing the Royal association with the college over the years. The event concludes with expressions of gratitude and hope for continued association.

What does the unveiling of the plaque signify?

How does the speaker express gratitude in the text?