Pont Street runs between the highly fashionable areas of Knightsbridge and Belgravia.
What exactly Julia Flyte and her friends have against Pont Street or its residents is not clear. Certainly, the examples given of what is Pont Street (wearing a signet ring; giving chocolates at the theatre; saying, 'Can I forage for you?' at a dance) do not have an immediate significance for the uninitiated.
Can anyone explain?
Nancy Mitford also used the term in her novel Love in a Cold Climate where the heroine's aunt is described as someone who tries to keep her nose firmly to Pont Street.