London

The Millennium Bridge
This 325m long steel bridge cost £18 million and was London's first new pedestrian river crossing over the Thames since the Tower Bridge in 1894. On its opening weekend in June 2000 when 160,000 people crossed over, the bridge developed a serious wobble and had to be closed for safety reasons. After a further £5m was spent on modifications, it finally reopened in February 2002.
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The Union Jack