They're more than twice the height of Nelson's Column - they've come halfway round the world - and they signal the latest stage of work on a project which will create 12,000 jobs.
Three cranes, the biggest ever seen in Britain, arrived from China this morning at the London Gateway in Essex.Our Political Correspondent Simon Harris explains exactly why they are here.
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The operation carried out by Westminster City Council led to the seizure of £8,000 worth of cigarettes.
Armed troops have been stationed around Parliament to free up armed police to patrol the streets in the wake of the Manchester bomb attack.
Chelsea had planned an open top bus tour to show off the Premier League trophy and hope to add the FA Cup in Saturday's final with Arsenal.