A 200-year-old mystery that links a castle in a German town, a mysterious 'Dark Countess' and the French royal family may be on the cusp of finally being solved. In 1807 a covered carriage arrived in the central German town of Hildburghausen. A man, now known to be Leonardus Cornelius van der Valck, a secretary in the Dutch embassy in Paris from July 1798 to April 1799, got out. With him was an enigmatic and secretive young woman who would go on to fire the imaginations of historians everywhere. End of the mystery? A digger clears the earth during the exhumation of the grave of so-called 'Dark Countess' in Hildburghausen, Germany
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Mysterious woman arrived in Hildburghausen in 1807 and lived in castle
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She always wore a veil or travelled in a covered carriage
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Some believe she was the real Marie Thérèse - daughter of executed royals
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They say her half-sister took her identity after the horrors of imprisonment
They are exhuming her grave to collect DNA evidence that can prove once and for all whether the @placeholder was in fact the ill-fated princess.