City bridges ​‘power down’ for first time for Earth Hour

Tower, London, Southwark, Millennium and Blackfriars bridges will turn off all non-essential, decorative lighting between 8.30pm and 9.30pm for Earth Hour this Saturday, 22 March 2025.

City Bridge Foundation, the 900-year-old charity which looks after the bridges at no cost to the taxpayer, will join organisations around the world in supporting the initiative organised by the environmental charity WWF.

Meanwhile, the foundation’s trustee, the City of London Corporation, will also turn off lights across some of its most famous buildings, including its own Guildhall headquarters, the Mansion House, home of the Lord Mayor of London, and Central Criminal Court – better known as the Old Bailey.

The initiative aligns with the City Corporation’s ambitious Climate Action Strategy, which the foundation has signed up to, and commits both organisations to achieving net zero carbon emissions in their own operations by 2027 and full value chain by 2040 – a decade ahead of national targets.

Simon Latham, City Bridge Foundation acting managing director, said: ​“As the custodian of five of London’s most recognisable bridges, Earth Hour offers us the chance to make a very clear and very visible demonstration of our commitment to climate action.

“We’re passionate about doing our part to tackle this issue through all areas of our work, including our bridge maintenance, our investments and our funding for charities across the capital.

“Climate action is the one issue above all which requires a co-ordinated response, so we’re delighted to be joining City Corporation colleagues to raise awareness of this issue by turning off the lights at some of the Square Mile’s most famous landmarks.”

City of London Corporation Policy Chairman, Chris Hayward, said: ​“Switching off the lights at some of the Square Mile’s most iconic landmarks – even for just an hour – helps to raise awareness of energy consumption and the urgent challenges facing our planet.

“As the governing body of the Square Mile, we have a duty to drive climate action, and we’re making real progress.

“Since 2018/19, we’ve cut our own net carbon emissions by 65% and reduced our value chain emissions by 23%. Our green spaces capture over 16,000 tonnes of carbon a year, and energy upgrades across our buildings will save over 1.5 million kWh annually.

“Our commitment to sustainability remains steadfast, and we will continue working with our partners across the City and beyond towards a greener, more resilient future.”

City Bridge Foundation has committed £1.2 million to the City Corporation’s total £68 million investment in its Climate Action Strategy, along with a further £5 million for building improvements.

The foundation has also made available a further £15 million for projects which support climate action, of which £1.4 million has already been allocated to work to identify ways of making its investment properties more energy efficient.

Meanwhile, Tower Bridge received a Gold Award from the member organisation Green Tourism in recognition of its sustainable practices, including through staff training, waste management, green procurement and energy efficient lighting.

The City Corporation has also been hailed as an ​‘A‑List climate action leader’ by global environment charity, Carbon Disclosure Project (CDP), receiving a top score on its climate action measures.

In addition, the organisation was ranked by Climate Emergency UK as one of the top 20 best-performing UK councils for its work in combatting climate change.

City Bridge Foundation is a world-class bridge owner responsible for five Thames crossings – including the iconic Tower Bridge – and London’s biggest independent charity funder.

Since 1995, we have awarded over £840 million to charitable organisations working to tackle inequality and injustice across London.

We have been bridging London and connecting communities for over 900 years. Our sole trustee is the City of London Corporation – the governing body for the Square Mile.

The City of London Corporation is the governing body of the Square Mile, dedicated to a vibrant and thriving City, supporting a diverse and sustainable London within a globally successful UK – www.cityoflondon.gov.uk