Telecommunications towers in the United Kingdom are operated mainly by Arqiva. Arqiva operates the transmitters for UK terrestrial TV and most radio broadcasting, both analogue and digital. BT also operates a number of telecommunications towers in the UK.
BT's towers were, at one time, the backbone for a national line-of-sight microwave telecommunications network. One of the most famous of these is the BT Tower in London. However, the introduction of fibre optic network technology rendered these microwave towers largely obsolete for their original purpose. Nowadays they tend to be used mainly for relatively low capacity fixed links to customer sites and mobile telephony.
BT Group owns at least 200 radio masts and towers in Britain. Of these, fourteen are reinforced concrete towers. The rest are of steel lattice construction.
Seven of the fourteen are of similar design, known as the 'Chilterns' type, after the first one which was built at Stokenchurch on the Chiltern Hills. They are identical except for their heights, which vary considerably. They are at:
The other seven are:
Below the level of the major telecommunications towers, mobile phone operators run roughly 23,000 base stations. In urban areas, these are almost all rooftop sites or microcells, but in rural areas these are often on towers, frequently owned by BT or Arqiva. The Sitefinder database is an incomplete list of mobile phone base stations in the UK. Since the discontinuation of the ofcom sitefinder website in 2015, Estate Systems Ltd have developed a comprehensive site www.mastdata.com for use by the by the public and Mobile Operators which locates masts within the UK and Northern Ireland.