A procession of 1,000 boats traveled down the Thames on Sunday June 3, 2012 to celebrate 60 years of Queen Elizabeth II's reign. Our contributor writes that "the event was very crowded so people had to struggle to get a view...[and] around the time the Queen passed by it started raining heavily."
In spite of the rain, however, organizers for the Queen's Diamond Jubilee estimate that over one million people came to catch a glimpse of the Queen, who traveled at the front of the 1,000 boat flotilla, in the Spirit of Chartwell, a red-and-gold barge.
The procession set a world record for the highest number of boats to partake in a river pageant. According to the official website for the Queen's Diamond Jubilee pageant, the event began at 2 pm and lasted until 6 pm. The boats began their journey at Battersea Bridge and finished at Tower Bridge.
For more information about the Queen's Diamond Jubilee pageant, read this article.