This has enabled passengers to travel up to 186 miles per hour from London St Pancras to Kent, Paris and Brussels, and has attracted at least £3.8 billion in economic and social benefits to Kent, London and the UK.

We are also celebrating this milestone, as we are High Speed 1's electrical infrastructure partner and the power behind the route that carries 75,000 train services and 20 million passengers each year, contributing to the success of High Speed 1 being the most reliable railway line in Europe.

This investment has seen outstanding results for the local and national economy. Research by Visit Kent and Destination Research Ltd this year identified leisure journeys increased nine-fold since the opening of the line, contributing £72 million to the region's visitor economy in 2017 alone, and an overall economic contribution of approximately £311 million.

Private investment in the electrical infrastructure of the line will also benefit the UK long-term, by deferring risk and public investment, where the assets will return to the UK Government in 2057.

As a strategic partner and a member of an ecosystem of suppliers to High Speed 1 and National Rail, we continue to operate and maintain the power infrastructure of High Speed 1, proudly contributing to the impressive reliability of the line – an average delay time of five seconds per train.

The electrical reliability is due to the innovative design, where the traction power design included the use of Static VAR Compensators, and value engineering reduced the number of physical sites for the National Grid connections from four to three.

This resulted in increased reliability of the electrical assets, reducing the overall costs for construction, maintenance, land purchases, planning, staff and insurance. These ideas and innovations earned us a British Construction Industry Major Power award.

We own and operate the power assets and systems, which gives the travelling public and High Speed 1 certainty over maintenance, whilst keeping the assets up to date with modern technology.

Safety is our top priority when managing the power infrastructure of High Speed 1 and impressively, we have had no accidents, which resulted in staff taking time off work, during more than seven years of operating the line.

Ian Smyth, Director of UK Power Networks Services, said: "From the initial design, to project management, financing, and the construction of the electrical assets of High Speed 1, we are proud to have contributed to the success of Europe's most reliable railway.

"We continue to invest in the training and development of engineers working along the route, which has provided the opportunity for apprentices to move through technical roles to operational high-voltage engineering roles. This dedication will continue for at least the next 40 years.

"By investing in local projects and local people, we're helping the ongoing growth of local employment across Kent and London for decades to come. This ensures High Speed 1 will continue to meet the needs of its domestic and international customers, and that the UK has a safe, efficient and reliable high-value asset.

"As the industry turns its attention to future high speed rail projects, we have learnt from the success of High Speed 1 and know the huge potential that private investment and innovation can bring to national infrastructure projects."