London ( CNN ) -- The Thames became a sea of red , white and blue Sunday , as tens of thousands celebrated the diamond jubilee of Queen Elizabeth II -- so perhaps it was only fitting that alongside all the flags , another great British tradition was very much in evidence : Gray skies and rain . Some 20,000 people took to the water aboard 1,000 vessels for a river pageant featuring dragon boats , a floating belfry and the royal barge . The event -- inspired by regal riverside celebrations of the past -- was the largest such celebration on the Thames for hundreds of years . Around a million people were expected to line the route to cheer on the queen , at the head of a seven-mile long flotilla . But bad weather meant a planned fly-past was canceled . Follow CNN 's live blog . Isabella Hales and her family staked out their claim to a spot near Tower Bridge -- where the festivities reached a climax on Sunday evening . `` It 's cold , but I do n't mind , '' the 10 year old , wearing a cardboard Duchess of Cambridge mask that was rapidly dissolving in the drizzle , told CNN . `` It was raining for the queen 's coronation too . I 'm just really excited , I ca n't wait . '' `` It 's only the second time someone has reigned for 60 years , '' her aunt Laura Hales added . `` It 's a big accomplishment , and we wanted to celebrate that . `` There are about 20 of us -- we 've come well prepared , '' she said , pointing out picnic supplies , party masks of the royal family -- including a corgi -- and pink champagne , `` And we do n't care what the weatherman says . `` Here 's to Liz ! '' she toasted , raising her glass . iReporters celebrate Queen Elizabeth II . Margaretta Soulsby , from Dorset , was the first to arrive at Tower Bridge on Saturday . She had planned to camp out , but when it began raining , stewards persuaded her to spend the night in a tent nearby . Soulsby told CNN it was `` well worth it -- I 'm in the perfect position , '' and said such events made her very proud to be British . `` In 1935 , when I was 10 , my father took the family to The Mall to watch the silver jubilee celebrations for King George V and Queen Mary , and I 've been privileged to be present at all of the major royal events since then . '' After gathering upriver in west London , the flotilla made its way from Battersea Bridge to Tower Bridge , passing through the heart of Britain 's capital city over the course of several hours . At the front were 300 man-powered boats , with thousands of volunteers propelling them down river , flags and streamers fluttering around them . A barge carrying the eight Royal Jubilee Bells -- the largest of which , at nearly half a ton , is named for the monarch -- led the way , with peals of bells ringing out from church towers along the river . Bumming a smoke from the queen : When the security bubble bursts . Next came passenger boats , pleasure boats , historic wooden vessels -- the oldest built in 1740 -- and boats carrying members of the armed forces , police and fire services . One of the boats taking part , the Amazon , also took part in the 1897 Diamond Jubilee celebrations for Queen Victoria , Britain 's longest-serving monarch and the only other to reach the landmark 60 years on the throne . The biggest cheers were reserved for the present queen , who was carried aboard a specially-converted royal barge , opulently draped in red and gold . Sailing boats that were too tall to pass under the 14 bridges along the river pageant route lined the river from London Bridge to Wapping , in the east , creating an avenue of sails set against the Tower of London and the city 's financial center . The queen disembarked at Tower Bridge and looked on as the remainder of the river pageant passed by in a riot of color and noise . Excitement grew as a gun salute rang out from the Tower of London . Nearby , those not lucky enough to get a riverside spot before the area was locked down , watched the pageant on a big screen . Cheers , whistles and the odd chorus of `` God Save the Queen '' rang out , and the crowd stayed jolly despite the rain . Helen McKee , from Kent , said she bought her family along to enjoy a once-in-a-lifetime spectacle . `` We 're never going to see this sort of thing again . I 've got a little boy and I thought it was important for him to see it . I still remember the Silver Jubilee in 1977 . It 's a great atmosphere here , everyone is so friendly . '' To Jamie Newell , from London , events on the river were just a forerunner of the main attraction of the day - the after party he was planning at home . Newell , decked out from head to toe in Union flags , and sporting red , white and blue contact lenses , said simply : `` I love the queen . '' Not everyone was of the same opinion . In a street behind the London Assembly building , scores of pro-republican campaigners had gathered , waving placards reading : `` Make monarchy history '' and `` Do n't jubilee-ve it '' and chanting `` Monarchy out , republic in . '' Today though , they seemed resigned to the fact that they were well and truly in the minority . As the queen 's barge approached and Tower Bridge lifted in salute , red white and blue streamers were tossed from the crowd . And then , as if on cue , the heavens opened , rain lashing those gathered on the riverbanks below . Hoods and umbrellas went up , coats and ponchos went on , quickly followed by shouts of `` brolleys down '' from those behind . Some of those who had gathered fled to shelter , but others remained determined to see out the whole seven-mile flotilla , even in torrential rain . Patrick Gunning had been waiting for the flotilla since 11 a.m. on Sunday . It was well worth the wait , he said . `` I 've had my son Saul , who 's 8 , on my shoulders so we saw the whole thing , and we 'll be staying a little longer . '' London 's Metropolitan Police said as many as 6,000 extra officers were on patrol during jubilee events . The huge security operation comes as London prepares to host the 2012 Olympic Games , which open in late July . Outside the capital , Britons gathered for thousands of jubilee-themed street parties and barbecues Sunday . Stores have been filled for weeks with an array of patriotic paraphernalia , from flag-adorned teapots to aprons to picnic sets , to help hosts set the scene for what is billed as a national celebration . The celebrations continue on Monday and Tuesday , which have been declared public holidays to mark the diamond jubilee . An afternoon garden party at Buckingham Palace will be followed Monday evening by a televised pop concert outside the palace grounds . At the end of the concert , the queen will take to the stage to light the `` National Beacon , '' which will be on the Mall . She will use a diamond made from crystal glass , which has been on display at the Tower of London from the beginning of May , to light the flame . More than 4,000 beacons will then be lit in communities throughout the United Kingdom , along with the Commonwealth and UK Overseas Territories . Tuesday will be a day of pomp and ceremony , as the queen attends a service of thanksgiving at St. Paul 's Cathedral , followed after lunch in Westminster by a carriage procession back to Buckingham Palace , where she will appear on the balcony , flanked by members of the royal family .
Diamond Jubilee of Britain 's Queen Elizabeth II marked with river pageant . Tens of thousands celebrate along the banks of the Thames . Royal family led flotilla of a thousand boats up river to Tower Bridge . Music and fireworks , street parties and festivals to mark 60th anniversary .