We think of London as a modern city, but did you know there are still around 1,500 gas street lights in operation here?
200 are in private hands, while responsibility for the other 1,300 lies in the hands of just four employees of British Gas. They have a territory ranging from Richmond Bridge to Bromley-by-Bow, although it's mainly concentrated around Westminster and Covent Garden.
We met up with two of the gas lamp lighters, responsible, not only for keeping the gas lamps alight, but also for maintaining and cleaning them. That includes fixing them when they're struck by vehicles.