The event is being staged to mark the 100th anniversary of the birth of Alan Turing, the man credited with more or less inventing the concept of the computer.
The Queer British Art show is being staged to mark the 50th anniversary of the decriminalisation of male homosexuality in England and Wales.
The event was staged to mark the anniversary of the Michael Kors brand, which he continued to build even while he was in Paris as design director of Céline from 1997 to 2003.
The rally was staged to mark International Women's Day and dedicated to honoring the memory of both women and men killed in clashes with security forces during Egypt's revolution.
The production was staged to mark the centenary of the Titanic disaster.
In Battersea Park, a right royal "knees-up" was staged to mark the Jubilee.
A series of events are being staged to mark the 10th anniversary of a Shropshire visitor centre.
The protests were staged to mark the fourth anniversary of Egypt's 2011 uprising, which toppled long-time leader Hosni Mubarak.
The concert was staged to mark the unveiling of a bronze statue of Lynott on Dublin's Harry Street in the city centre.
The somewhat nebulous demonstration, now in its third day, has been staged on Mohamed Mahmoud Street to mark the anniversary of the eponymous battles that took place here last November, when more than 40 people were killed and scores seriously injured.
