Belfast City Council has many signs up round the city centre explaining the history and background to various local landmarks. Sadly, not always do those responsible proofread them before they are erected.

The board beside Laganside Courts has a somewhat glaring error on it.

Have a look here

Royal titles and styles are really not that hard (at least not now) in the United Kingdom.

• The Sovereign is Her Majesty (or His Majesty when male).
• Other Royal Princes and Princesses are styled Royal Highness (His/Her Royal Highness).

Therefore, in the example above, HRH Queen Elizabeth is wrong. Since birth, Her Majesty has had several styles:

• HRH Princess Elizabeth of York, 21 April 1926 – 11 December 1936
• HRH The Princess Elizabeth, 11 December 1936 – 20 November 1947
• HRH The Princess Elizabeth, Duchess of Edinburgh, 20 November 1947 – 6 February 1952
• HM The Queen, 6 February 1952 to present.

Quite how this is so difficult to understand, I do not know.