William Cobbett disliked the rapid growth of London and nicknamed it The Great Wen, comparing it to a sebaceous cyst.
The Great Wen is a disparaging nickname for London. The term was coined in the 1820s by William Cobbett, the radical pamphleteer and champion of rural England. Cobbett saw the rapidly growing city as a pathological swelling on the face of the nation. (A "wen" is a sebaceous cyst.) 
