Rhodri Marsden's Interesting Objects: The monstrous carbuncle

Prince Charles compared the proposed extension to the National Gallery to what Webster's describes as "a very painful acute local inflammation of subcutaneous tissue" (Royal Institute of British Architects)

* Thirty years ago this morning, Britain began its relationship with the phrase "monstrous carbuncle". The previous night, Prince Charles had delivered a speech at Hampton Court Palace to commemorate the 150th anniversary of the Royal Institute of British Architects (RIBA). He seized the opportunity to compare the proposed extension to the National Gallery to what Webster's describes as "a very painful acute local inflammation of subcutaneous tissue".

* The "monstrous carbuncle" itself was meant to occupy space that had been vacant since Hampton's department store was flattened by a bomb in 1940. It was designed by Ahrends, Burton & Koralek, and was submitted along with 78 other entries as part of a competition. Following an exhibition of the designs, ABK made a shortlist of seven – along with Richard Rogers, who later explained the inherent problem. "Thatcher insisted that the extension be paid for by private development," he said. "A commercial building had to fit on the site." ABK's vision included a 92-foot glass tower of offices.

* ABK was announced as the winner in October 1982 on the condition that changes were made to its design, but they nevertheless felt that the firm "had the best chance of designing a successful building". The new design was given the green light – but Charles turned it red. The following year a new, closed competition was launched with an office-less brief, thanks largely to a £50m donation from the Sainsbury family. The winner, by Robert Venturi, opened in 1991.

* Shortly after Charles's speech, Peter Ahrends invited him to ABK's office to discuss, among other things, the monstrous carbuncle. In an interview with the Islington Tribune, Ahrends recalled Charles saying, as he left, "I'm sorry it had to be you".

@rhodri