The Traffic and Environmental Zone, commonly known as the "ring of steel",[1] is the security and surveillance cordon consisting of road barriers, checkpoints and several hundred CCTV cameras surrounding the City of London, the financial district at the heart of Greater London. The measures have been used since the 1990s to deter terrorism and other threats.[2][3]
- ^ "Improving access for cyclists". Transport for London. Retrieved 31 May 2018.
- ^ City of London Police. "3.2.4 The automated number plate recognition (ANPR) system and the Corporation of London’s traffic and environment zone culminate in what is generally referred to and known as the ‘ring of steel’.
- ^ BBC News (2003-12-08)