Nelson's Column is a monument in Trafalgar Square in central London built to commemorate Admiral Horatio Nelson, who died at the Battle of Trafalgar in 1805. The monument was constructed between 1840 and 1843 to a design by William Railton at a cost of £47,000. It is a column of the Corinthian order built from Dartmoor granite. The Craigleith sandstone statue of Nelson is by E. H. Baily and the four bronze lions on the base, added in 1867, were designed by Sir Edwin Landseer.

The pedestal is decorated with four bronze relief panels, each 18 feet (5.5 m) square, cast from captured French guns. They depict the Battle of Cape St Vincent, the Battle of the Nile, the Battle of Copenhagen and the Death of Nelson at Trafalgar.

It was refurbished in 2006 at a cost of £420,000, at which time it was surveyed and found to be 14 ft 6 in (4.4 m) shorter than previously supposed. The whole monument is 169 ft 3 in (51.6 m) tall from the bottom of the pedestal to the top of Nelson's hat.

The column has famously been climbed on several occasions as a publicity stunt to draw attention to social or political causes.