The final chapter of a long-running documentary series charting the launch of the long-delayed and over-budget Elizabeth line railway will air next month.

The Fifteen Billion Pound Railway: Inside The Elizabeth Line will be broadcast on June 12 on BBC Two, less than a month after the service opened.

Filmed over 10 years, the programme will capture the journey of engineers, technicians and transport staff who came under increasing pressure to deliver the project as they faced multiple logistical challenges.

It will feature interviews with people including Crossrail’s chief executive Mark Wild, head technician Pradeep Vasudev and train driver Emma Knowles.

The railway, which has cost at least £18.9 billion, stretches 75 miles across London and the South East and is one of the most ambitious engineering feats in Britain since the time of noted architect Isambard Kingdom Brunel.

More than a million journeys were made on the central section of the Elizabeth line in the five days after it opened on May 24.

Around 130,000 people travelled on the service in its first few hours of operation, with hundreds of transport enthusiasts queuing from the early hours to be on the first trains.

The service is initially operating in three separate sections, which are expected to be integrated in the autumn.

Demand for the railway has been hit by the coronavirus pandemic.

Transport for London estimates that annual passenger numbers will not reach 170 million by 2026.

Before the virus crisis, it expected the line to carry more than 200 million passengers annually.

The new central section, built by the Crossrail project, runs through tunnels from Paddington to Abbey Wood.

It will initially be closed on Sundays, apart from during the Platinum Jubilee weekend, to allow for further testing and software updates.

Crossrail suffered numerous issues including construction difficulties and complications installing signalling systems.

It was due to be completed by December 2018 and was set a budget of £14.8 billion in 2010.

The final total has been estimated at £18.9 billion.