They say you shouldn’t rekindle old romances, that a distant memory is rosier than reality ever was. It is perhaps a thought which should have entered somebody’s mind at Westminster council when procuring, planning and budgeting their Marble Arch Mound.

The mound is an updating of a 2004 project by the same architects, MVRDV, originally designed to be that year’s Serpentine Pavilion. It would have totally entombed the gallery within a man-made mountain. The project never started, costs were as steep as the intended slopes and, in the words of then Serpentine director Julia Peyton-Jones, it was an “heroic failure”, consigned to the archives, existing only as a romantic what-if?

“Half a lifetime ago – 35 years, to be exact – I met and fell in love with my first love,” wrote a married middle-aged man to the Guardian’s relationship advisor Mariella Frostrup. “We spent a year together before, out of the blue and with no forewarning, she finished it … My heart shattered into a thousand pieces, and it has never mended.” He was wondering if he should get back in touch. It would be a leap to suggest the letter writer’s name was Melvyn Caplan, but the author does perhaps share some DNA with the recently resigned deputy leader of Westminster council. It was he who led the charge to rekindle the romantic Serpentine “failure” and relocate it alongside the already oppressed Marble Arch.

According to urban myth, the French writer Guy de Maupassant used to daily dine in a restaurant at the foot of the Eiffel Tower because it was “the only place I can’t see the damned thing”. The quip’s factual accuracy is up for debate, but de Maupassant was clearly no fan. He wrote in The Wandering Life that he left Paris because not only could the “skinny pyramid of iron ladders” be seen from every street, but its image was recreated “in every material known to man” and displayed in shop windows across the city as “a perpetual nightmare”.

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