the knowledge

The Knowledge is the in-depth study of London street routes and places of interest that taxicab-drivers must complete to obtain a licence to operate a black cab. It was instigated in 1851, and has changed little since. It is the world's most demanding training course for taxicab-drivers; and applicants will usually need at least 12 'Appearances' (attempts at the final test), after preparation averaging 34 months, to pass the examination.