Fourth Plinth

Stand in Trafalgar Square in the City of Westminster and you will see a plinth at each corner. Sir Charles Barry, who also worked on the Palace of Westminster, completed the square in 1845. Nelson's Column rises at its centre, commemorating the admiral who died at the Battle of Trafalgar in 1805. Three of the corners hold statues of King George IV, General Sir Charles James Napier and Major General Sir Henry Havelock. The Fourth Plinth itself was built in 1841 for a statue of William IV, but the money ran out. So it stood empty for more than 150 years while London debated what belonged there.

In 1999 the empty plinth took on a new job: a changing series of temporary contemporary artworks. The Greater London Authority runs the programme, and each work stays only until the next one arrives. Artists such as Mark Wallinger, Rachel Whiteread, Bill Woodrow and Antony Gormley have shown work on it. Past commissions range from a life-sized Christ figure to a giant blue cockerel. Another put a replica of Nelson's ship inside a bottle. One handed the plinth to the public, who took turns standing on it for an hour each.

Teresa Margolles, a Mexican artist, created the installation Mil Veces Un Instante. She trained as a forensic pathologist and worked as a mortician in Mexico City. The piece casts the faces of 726 transgender and non-binary people in plaster applied directly to their skin. Many of the people cast are sex workers. Around the plinth the casts form a tzompantli, the skull rack that Mesoamerican civilizations raised for war captives and sacrificial victims. The plaster still holds traces of their hair and skin, so each cast carries its sitter into the square. The three statues across the square keep their poses, but the fourth corner stays open to whoever comes next.