A fully functioning toilet is to be unveiled as a public piece of art.
The person inside the cube can see passers-by but is invisible to them
Artist Monica Bonvicini has created a minimalist glass cube containing a usable loo to stand opposite the Tate Britain gallery in London.
The work, called Don't Miss A Sec, is made out of one-way glass which means you can see out but not in.
The public sculpture will sit at the former Royal Army Medical College in Millbank, and is meant for public use.
A spokeswoman for the project said: "It will arouse curiosity because people can just come and use it, although there is a question of whether people will feel comfortable doing so.
"They may be wary of desecrating a work of art or may be uneasy that because they can see out, other people can see in."
The Italian born artist, who is based in Los Angeles, is known for making viewers of her work question their environment.
She has installed a prison toilet in the cube which is a reference to an old use of the area.
Bonvicini's toilet will be free to use and opens for two hours from 6pm each weekday
On Saturdays it can be used from 2pm to 6pm and 10am to 6pm on Sundays
It can also be opened by appointment
It once housed Millbank Penitentiary where prisoners were held prior to being put on ships and transported to Australia.
The site closed as an army medical hospital in 1975 but continued to be used by the military until 2000.
It will become home to Chelsea College of Art and Design in autumn 2004.
Her work is a collaboration between Broadway Projects Trust, the London Institute, Chelsea College of Art and Design and architects for the site, Allies and Morrison.