The massive restoration project for the Elizabeth Tower (which houses the bell known as Big Ben) concluded with a final cost of approximately £80 million (roughly $100 million USD). When the project began in 2017, the original estimate was just £29 million, but the bill skyrocketed as surveyors discovered extensive damage to the Victorian stonework, intricate clock mechanisms, and roof plumbing that had not been touched in over 160 years. The refurbishment involved cleaning and repairing thousands of pieces of "Anston" limestone, reglazing the clock faces with mouth-blown glass, and restoring the clock's hands to their original Prussian blue color. While the high price tag was a point of political debate in the UK, the restoration is expected to preserve the landmark for at least another 60 years, ensuring the "Bong" of the 13.7-ton bell continues to be a symbol of London for generations to come.