The "Angel of the North" was commissioned by Gateshead Council and created by internationally renowned sculptor Antony Gormley. It is Britain's largest sculpture and believed to be the world's largest angel scupture. It is one of the most-viewed pieces of art in the world - seen by more than one person every second, 90,000 every day or 33 million every year.
Work on the sculpture started in July 1997 and it was assembled on site seven months later in February 1998.
The Angel was fabricated from 200 tonnes of Corten weathering steel by Hartlepool Steel Fabrications Ltd on Teesside. It rises 20 metres (65ft) and has a wing span of 54 metres (175 ft) - almost as big as a jumbo jet.
"People are always asking why an angel? The only response I can give is that no-one has ever seen one and we need to keep imagining them.
The angel has three functions: firstly a historic one to remind us that below the site coal miners worked in the dark for two hundred years, secondly to grasp hold of the future expressing our transition from the industrial to the information age, and lastly to be a focus for our hopes and fears."
Antony Gormley, sculptor.
The Angel has an external skeleton of ribs cut from 50mm thick steel with the skin in 6mm sheet steel bent and welded to form the body shape.
Ove Arup and Partners acted as technical experts on the design and the site, and the foundations were prepared by Thomas Armstrong (construction) Ltd.
The site was cleared, old mine workings were filled with grounting and eight holes drilled, each 3/4 metres across.
One hundred and fifty tonnes of concrete were poured around steel reinforcement to form massive piles to root the sculpture into solid rock 20 metres below ground.
A concrete slab one and half metres by 8 metres was the laid on top of the piles. A plinth 5.3 metres high was built on the slabs and cast into it are 52 bolts - each three metres long - onto which the Angel is fixed.