Crowds gather to see Julian Harrap's new design winched into place atop 61m column

A new viewing platform has been winched onto the Monument - the 61m-tall stone column near London Bridge that commemorates the 1666 Great Fire of London - as part of a £4.5m project funded by the City of London Corporation.

Streets around the City were blocked off on Saturday for installation of the platform balustrade and cage, designed by Julian Harrap Architects. Made of lightweight cable mesh stretched over stainless steel tubes, it replaces a fifties-built structure of iron bars.

Crowds gathered to watch the delicate operation, which took several hours, as a huge crane winched the new structure into position on the black limestone viewing platform.

The 2mm-thick stainless steel cable mesh will later be stretched over the outside of the cage frame and inside the balustrade, then woven onto 8mm-thick stainless steel rods welded to the structural elements.

Judy Allen, project architect, said the aim was to improve the experience of the visitor. “The previous cage, of iron bars, felt like a zoo enclosure,” she said. “A mesh was finally specified with an aperture of less than the diameter of a drinks can, yet strong enough to resist the pressure of people leaning against, hanging from or cutting through it. The lightweight cable mesh almost disappears when looking through it.”

Those who climb the 311 spiral steps to admire the view will also be able to use state-of-the-art telescopes designed as part of the new balustrade.

The curved stainless steel tubes of the structure contain electrical cabling for the services on the platform, including CCTV cameras and lighting.

CWO is the specialist stonemasons and principal contractor.