LONDON -- It's not the type of welcome most wedding guests expect before they get into church -- background checks, ID verification and a security sweep.
But then again, Prince William and Kate Middleton's wedding on Friday is no ordinary affair.
Britain hasn't seen a royal wedding of this size since Prince Charles married Diana in 1981 -- there were actually 200 more police on duty for that wedding, which had a longer procession route and a guest list of some 3,500 people, including foreign royals and heads of state.
Friday's wedding will offer much of the same pomp and circumstance with its 1,900 invited guests, but it also presents a modern security nightmare for the 5,000 U.K. police officers on duty. Police will be on the look-out for Irish dissident terrorists, Muslim extremists, anti-monarchists and protesters.