I ate up Peter Ackroyd's London Under: The Secret History Beneath the Streets with a spoon.
Well, not literally. But it was a slim little book that I enjoyed very much, about one of my very favorite cities in the world. Ackroyd relates short histories and anecdotes about the messy and historical business under London's streets: its sewers, buried rivers, water pipes, tunnels, and the Underground (to name just a few of his topics). At around 200 pages with generously spaced text, it was the perfect little morsel to get me through a couple of days when I couldn't find much else I wanted to read.
It's not perfect; it ends rather abruptly and it moves from subject to subject without much rhyme or reason, but if you're at all interested in urban planning, history, or London itself I think you'd find this book very interesting:
"The sewers of early medieval London were the streams and rivers that ran down to the Thames. Cess-pits, lined with brick or stone, were also in common use and were cleansed weekly or fortnightly by urban workers known as 'gong-fermers.' In 1326 one of them, 'Richard the Raker,' fell into his own cess-pit and suffocated 'monstrously in his own excrement.' The first pipes to carry waste, in an underground drainage system, were introduced to London in the thirteenth century during the reign of Henry III." (p. 80.)
Okay, that's not a pleasant image. But Ackroyd most definitely has painted an image. And that's what blows my mind about London, and other really old cities. 1326! Just imagine. I want to keep imagining--and that's why I'm going to look into another of Ackroyd's history books: London: A Biography.