London Bridge hasn’t fallen down–yet. But any 117-year old bridge is bound to need a few updates here and there. The latest round of improvements will help cut the amount of energy required to light the landmark by 40 percent. There’s no denying that London Bridge is an icon–a song praising its usefulness in times of conflict is sung to children before they can walk. But in recent iterations, the bridge has incorporated inefficient technologies that mar its noble history.