How did the lights of Trafalgar Square look in 1845? Where were London's first homes with electric lights? Where does London have an eternal flame as a war memorial? How and where can you spot a gas light today? What on Earth is the Meridian Laser?
Now we've entered that time of gloomy evenings, we thought we'd map the history of lights in London. From the 1680s, when householders were obliged by law to hang lanterns outside their house — right through to green lasers shooting through the ether — here are the lights that changed our city forever.
Explore the map, and prepare to be illuminated.