Prince Charles and Diana's wedding on 29 July 1981 at St. Paul’s Cathedral in London cost the equivalent of $70 million US Dollars (USD) in 2010s currency. The most significant expense of the British Royal wedding between the heir to the British throne and schoolteacher Lady Diana was security, which accounted for around $600,000 USD. Diana’s wedding dress was estimated to cost around $13,000 USD and had a 25 foot (7.62m) long train. While around 3,000 guests attended, the Royal Wedding was observed by nearly one billion television viewers and radio listeners. The couple’s marriage lasted 11 years, and they officially separated in 1992 and divorced in 1996, one year before Diana’s death in a car accident.
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