A large blue rooster currently stands on the fourth plinth at Trafalgar Square, which has become a showcase for temporary artworks.
Mayor of London Boris Johnson said: "The placing of challenging artwork amidst the historic surroundings of Trafalgar Square creates a delicious juxtaposition that gets people talking and debating, underpinning London's reputation as a great world city for culture."
Really Good, by David Shingley
Larger Squat Afar, by Mark Leckey
Gift Horse, by Hans Haake
Six artists have unveiled their vision for what they believe should take pride of place on Trafalgar Square's fourth plinth. Here are the first three.
The Dance, by Li liane Lijn
Unmade Monument, by Marcus Coates
Moon Mask, by Ugo Rondinone
London Mayor Boris Johnson has today unveiled a sculpture of a blue cockerel on the fourth plinth in Trafalgar Square.
The sculpture, created by German artist Katharina Fritsch, will remain in place for 18 months.
Trafalgar Square's Fourth Plinth will welcome its latest artwork today when a sculpture by German artist Katharina Fritsch is installed.
The sculpture, chosen from several shortlisted submissions, depicts a bright blue cockerel and will be unveiled by London Mayor Boris Johnson this morning.
The plinth has featured several high profile artworks since 2005, including a marble portrait of disabled artist Alison Lapper, portraying her as heavily pregnant.
Marc Quinn's sculpture of the disabled artist Alison Lapper was displayed from September 2005 until October 2007.
Lapper, who was born with no arms and shortened legs due to a congenital disorder, posed naked for Quinn when she was eight months pregnant.
"Alison Lapper Pregnant" was replaced with a very different artwork - an architectural model of a 21-story building.
The coloured glass sculpture by German artist Thomas Schutte, "Model for a Hotel 2007" was unveiled in November 2007 and occupied the plinth until the end of May 2009.
Next came Anthony Gormley's "One and Other" - a "living monument" which involved members of the public taking to the plinth.
The space was occupied by different people - chosen by ballot - every hour, 24 hours a day, for 100 days.
From 2010 to 2012, the plinth was home to Yinka Shonibare's "Nelson's ship in a bottle" which commemorated the Battle of Trafalgar.
And currently in position is a giant bronze sculpture of a boy astride a rocking horse. It is called "Powerless Structures Fig 101".