Only 1,900 people in the world will attend the most famous wedding of the century. Even fewer will attend a lunchtime reception thrown by Queen Elizabeth at Buckingham Palace—600, to be exact. An even smaller group of 300 is invited for dinner and dancing at the palace later in the day for an event hosted by Prince Charles. Those lucky enough to receive the pale brown envelopes on their doorsteps will be treated to the event of a lifetime, which is slated to be the most-watched televised event in Britain, ever.