The Ghost Map: The Story of London's Most Terrifying Epidemic – and How it Changed Science, Cities and the Modern World is a book by Steven Berlin Johnson in which he describes the most intense outbreak of cholera in Victorian London and centers on John Snow and Henry Whitehead.

The two central figures are physician John Snow, who created a map of the cholera cases, and the Reverend Henry Whitehead, whose extensive knowledge of the local community helped determine the initial cause of the outbreak.

Around the mid-1850s Snow figured out the source of cholera contamination to be the drinking water from the Broad Street pump.

[2] A review posted in the International Journal of Epidemiology was largely favorable, stating that "the single weakness of this book is a bewildering final section which attempts to apply John Snow's work to a long list of contemporary problems.

But for the reader prepared to put the book down at page 217, Steven Johnson has written a comprehensive, diversely sourced and insightful blockbuster account of a cholera outbreak in Victorian London.