London - A giant black container by leading Polish artist Miroslaw Balka in which visitors are left completely in the dark was unveiled as the latest piece of modern art filling the turbine hall of London's Tate Modern gallery Monday.

The steel sculpture, resembling a huge shipping container, is the latest in a series of bold installations that have filled the entrance hall of the Tate - a former power station turned into the world's top ranking museum of modern art.

Balka has named the piece How It Is, adopting the title of a Samuel Beckett novel.

Visitors enter the raised pitch-black container via a ramp and, once inside, hear their footsteps echo in the 30 metre-long chamber.

Gallery attendants will be on hand to supply torches should visitors feel panicky about being inside the space, exhibition organizers said.

"It's everything and nothing in a way ... You can shape this yourself. The shape you create is not just about your body, it's about your mind," Balka said at a news conference.

Asked how he felt on stepping inside for the first time, Balka said: "I used the word 'Whoa' - it works. I did not have this moment of not being prepared ... a moment of happiness came to me, it was not about fear any longer."

Balka, whose works often explore themes of personal history and contain frequent references to the Holocaust, said: "The 21st century - it's not so happy as we could suppose, so that's how it is."

The installation can be seen by the public from October 13 to April 5, 2010. (dpa)