Old Street roundabout as you know it will be no more from Bank Holiday Monday, when two-way traffic is introduced ahead of the huge project to pedestrianise the lethal junction.

TfL has announced road closures over the weekend in preparation for the switch, and warned people to expect delays and bus diversions.

From 9.30pm on Friday until midnight on Sunday the western stretch of Old Street and the southern section of City Road will be closed while the road layout is changed to two-way traffic.

Then, from Monday, the south-eastern section of the junction will be closed until November while a new entrance and subway is built in Cowper Street and a 24-inch water pump is diverted.

Two-way traffic will be in place on the rest of the outdated junction, one of the most lethal in London and the place where cyclist Sarah Doone lost her leg after being run over by a cement truck in August.

In November, the south-eastern arm will reopen for two-way traffic and the northwest arm of the junction will permanently close, creating a pedestrianised square.

Nick Fairholme, TfL's project director, said: "Our work will transform journeys for thousands of people and make it much easier and safer to walk, cycle and use public transport.

"The switch to two-way traffic is a major milestone and some road closures and changes to travel are needed. I'd encourage everybody in the area to take extra care as traffic gets used to the new road layout."

The project is expected to be completed in 2020. But the Gazette can reveal transport planners have ditched their design for a new Tube station entrance on the soon-to-be pedestrianised Old Street roundabout after it was panned by Hackney and Islington councils.

Both authorities questioned the lack of management plan for a giant set of stairs for people to sit on, fearing they could attract anti-social behaviour.

Hackney also took issue with the fact the only exit from Old Street into the borough was being removed, and anyone wanting to head into Hoxton or Shoreditch would have to cross six lanes of traffic first.

We understand new plans are being drawn up and will be published later this year.

Islington's corporate environment chief Kevin O'Leary said: "We're working with the mayor of London, TfL and Hackney to transform the outdated Old Street junction to give more priority to people instead of vehicles, creating a much better environment for pedestrians and cyclists. We'll continue to work in partnership to make sure disruption is kept to a minimum as work continues."

Victoria Lebrec, RoadPeace campaign coordinator, said: "The current layout is unsafe and we've seen some really horrible collisions happen there over the last few years.

"People walking and cycling should not feel like they are taking their lives into their hands when travelling through Old Street. At RoadPeace we see the devastation that road danger causes, and welcome TfL's commitment to addressing it."

Signed cycle routes are in place to help guide people through the area during construction work, including segregated cycle lanes and dedicated cycle signals for people cycling east-west through Old Street.

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