Royal Wedding: How a vast security operation will keep the couple, guests and spectators safe

File photo - Britain's Prince Harry and his fiancee Meghan Markle leave St Mary Magdalene's church after the Royal Family's Christmas Day service on the Sandringham estate in eastern England, Britain, December 25, 2017. The Royal Wedding this weekend will be spectacular and the vast security operation to keep the couple, their guests and the crowds safe will be a masterpiece of planning. Authorities in the U.K. have had to consider all potential threats and prepare solutions. Highly trained and experienced manpower, combined with a blend of low tech and high tech approaches will deliver a masterclass in how to keep a gigantic event safe - one highly attractive to terrorists, protesters and pranksters alike, and while the entire world is watching on their televisions. Keeping a Royal wedding safe is no small task.