London, like every city and town, is full of street lamps, some of which are affixed to buildings, while others sit atop lampposts.
While the majority of these are powered by electricity a small percentage are still powered by gas, like the one below..
However, unlike anywhere else that I know of, London also has taxi call lights. These call lights are usually attached to hotels, private residences and the occasional Government building, like the one below at the Palace of Westminster.
