The structure was hoised into place with ropes. Pic by Richard Davies
Volunteers have been getting their hands dirty for a project to celebrate London's architecture festival.
Architects Foster and Partners came up with a design which people were then invited to make handprints on before helping raise the structure into place.
The conical installation, which is more than 10m (32.8ft) high, is made of netting, fabric panels and rope.
It will remain in Exhibition Road, Kensington, west London, until later when it will be dismantled.
Alistair Lenczner, of Foster and Partners, said it was all about celebrating the human contribution to architecture.
"We wanted to create something which showed that architecture was the result of a collaboration of many people," he said.
Throughout the day people can walk through the structure and experience an interactive sound sculpture created by artist Bill Fontana.
During the morning people were asked to put their handprints on diamond-shaped fabric panels which formed part of the installation.
Then at 1400 BST the structure was hoisted into place by people pulling, in a tug-of-war style, on ropes.
The event marked the launch of the 2008 London Festival of Architecture which runs until 20 July.