Boldyn Networks has expanded its deployment of mobile connectivity across the entire London Underground network.

Neutral host provider Boldyn said more than half of London's 'underground' Tube stations have started to receive mobile coverage in their ticket halls, corridors, and platforms.

In total, 62 out of the 121 Tube stations located underground have been connected, along with the entire Elizabeth Line.

Boldyn was awarded a 20-year concession by TfL in June 2021 to provide high-speed, 5G-ready mobile coverage across the entire London Underground network.

All four UK operators, Vodafone, Virgin Media O2, BT (EE), and Three have provided their own network coverage on top of the network hosted by Boldyn.

Battersea Power Station is one of the latest underground stations to go live with 4G and 5G mobile coverage, with DCD invited on a press tour of the network facilities installed at the station earlier this week.

More tube stations will be connected in the coming months, noted Boldyn, including King’s Cross St Pancras, Gloucester Road, Warwick Avenue, and Vauxhall.

According to Boldyn, work is underway to extend coverage in the tunnels along Tube lines, with the vast majority of the Northern and Metropolitan lines due to have coverage in the tunnels by the end of summer 2026, while the project remains on track for the whole Tube network to have mobile coverage by the end of this year.

“A project of this scale demands extraordinary engineering effort and close-knit collaboration with TfL, with work often carried out overnight in one of the world’s most complex transport networks," said Nick Hudson, chief operating officer for the UK and Ireland at Boldyn Networks.

Boldyn noted this week that the window of opportunity to carry out work on the deployment is often limited to around four hours a night.

In total, around 400 engineers are regularly working on the project overnight, delivering the project during the limited overnight engineering hours on the Tube network. Fiber cabling has already been installed throughout the tunnels across the London Underground.

Once fully delivered, more than 2,000 km (1,242 miles) of cabling, plus thousands of radios, are expected to be installed within tunnels and stations, all of which will be fitted outside of operational hours.

Boldyn hosts its equipment in cabinets within specific rooms in the back end of the station, while mobile operators' equipment is hosted at base station hotels around London. These are able to connect to the in-station cabinets via fiber. There are nine base station hotels in total.

DCD will cover the tour in full detail in Issue 60 of DCD>Magazine.