The giant grey-black work, based on a human form lying down, is entered via the right "foot", and combines the fun of an adventure playground with the unnerving quality of a labyrinth often plunged into darkness.

For the first time, the Turner Prize-winning artist who has always been preoccupied with the human form allows us to get inside, and draws parallels between the body and the architectural spaces we inhabit.

"I think we dwell first in this borrowed bit of the material world that we call the body," Gormley told Reuters, standing beside the imposing structure made up of interlocking blocks.

"It has its own life that is unknowable. But the second place we dwell is the body of architecture, the built environment," he added.

"We're the most extraordinary species that decided to structure our habitat according to very, very abstract principles of horizontal and vertical planes."

Model has plenty of surprises. The more nimble visitor can crawl through its left "arm", which is a passage around three feet high, or clamber on to a roof bathed in light.

"There are places that you wouldn't necessarily know are there," Gormley said. As if to prove his point, he disappeared into a large raised "aperture" invisible in the darkness.

Sound also plays a part, with the resonance of voices and rumble of footsteps giving clues to the size of each space.

PLAYGROUND

The artist said he encouraged people to explore the work rather than just look, unlike most sculptures which are strictly off-limits.

"Psychological architecture suddenly starts to reverberate with human life," he explained, adding that the sense of unease when entering the dark spaces was part of its appeal.

"I think creepiness is good," he said in the pitch-black "head". "I think it's necessary to get under people's skin. You don't want them to easily ingest or accept something."

Several times he referred to the Seagram murals of American painter Mark Rothko, works that inspired him as an artist and which he had in mind while making Model.

"Their surfaces give you this idea of space, or an invitation, they seat you at a threshold and allow you to dream of what exists beyond that threshold," he said.

"You could say this is the literal version of that."

Gormley, born in 1950, won the Turner Prize in 1994 and is probably best known for his 20-metre high public "Angel of the North" sculpture located near Newcastle in northern England.

He would not say what price the White Cube gallery had put on Model, and the gallery itself could not immediately provide a figure when asked, but Gormley has become one of the most sought-after British artists at auction.

A life-size iron maquette for Angel of the North fetched 3.4 million pounds at an auction at Christie's in October last year.

Early critical reaction to Model was mixed.

"We think of the pyramids, of tombs in lightless spaces," wrote Michael Glover in the Independent. "We have entered this space hoping for a visceral response of some kind, but it never quite happens."

Model is on display at White Cube, Bermondsey, until February 10, 2013. (Reporting by Mike Collett-White, editing by Paul Casciato)

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