One of the most popular attractions at Toronto City Hall is the nail mural located on the east wall near the main entrance.

This mural, called Metropolis, was the winning entry in an art competition held in 1974 to select a permanent work of art to complement City Hall's unique architectural style. Metropolis was installed in 1977.

The work is a symbolic intrepretation of a great city (or metropolis), but not of any particular city. Created from 100,000 common nails, the mural is made up of nine panels, each weighing about 180 kilograms. The circle of massed copper nails in the centre represents the heart, or downtown core, of the city.

The artist is David Partridge. Originally from Akron, Ohio, Mr. Partridge came to Canada in 1944. He studied at the University of Toronto, and also at Queen's University in Kingston, Ontario.