Lampposts, also called lamp posts, (PROSE: Knock! Knock! Who's There?) were silver, metal poles with fluorescent lights placed under a curve at the top, and were used to illuminate streets. They were an updated version of the gas lanterns (AUDIO: The Lichyrwick Abomination) used in the 19th century. (COMIC: The Curious Tale of Spring-Heeled Jack)
According to a joke book which the Doctor and Yaz became trapped within, the Second Doctor and Jamie once visited a moon base, which Jamie thought was "incredible", as he could jump "higher than a lamp post!". The Doctor remarked that he should think so, as lamp posts couldn't jump. (PROSE: Knock! Knock! Who's There?)