Royal fans were left in awe after a new ITV documentary revealed that Prince Charles almost married his third cousin.

The documentary called The Queen & Her Cousins dived into the lives of the Queen and her family, including Princess Olga Romanoff, whose the grand-niece of Tsar Nicholas II of Russia.

Olga Romanoff is the third cousin that was considered to be a suitable bride for Prince Charles as she had "An title. Foreign. Breeding. And possibly because I was 17 and they were all quite young, virginity was good. I was so virginal!"

It wasn't meant to be as Prince Charles quickly matched with Diana Spencer, who was the daughter of family friends instead of his cousins.

Prince Charles first met Diana when he was 29 and she was 16, as the prince was friends with her older sister.

It wasn't long before Prince Charles announced his engagement to Lady Diana, but the pair had only met 12 or 13 times before he proposed.

Despite being married on July 29, 1981, the marriage was plagued with infidelity rumours and the pair split in 1992.

They were divorced in 1996 and Princess Diana was killed in a car crash in Paris when her sons Prince William and Prince Harry were only 15 and 12.