'City of Light', 'City of Mystery', 'City of Romance' – of course, it must be Paris. No other European capital city has the same allure, charm and plethora of pleasures to be searched for and delightfully discovered. For while Paris’s public buildings are there for all to admire, there is another, more secret Paris that is not so easy to find. Unlike London, or many other busy cities, Paris has always hidden much of its domestic charm behind tantalisingly closed doors – heavy wooden doors – that can only be accessed through keys, codes or the interrogation of suspicious concierges. Behind those doors are houses and apartments grouped round courtyards and gardens, which remain unseen by all except for those in the know, until now.