For London's Cabbies, Job Entails World's Hardest Geography Test 12 years ago
AFAIK, NYC cabbies just have to do a 6 hour driving course, no knowledge of city geography required. (http://on.nyc.gov/WHwxgi)
Which is why there are 6x as many complaints-per-taxi about NYC taxis vs London taxis:
http://learntheknowledge.co.uk/learning-the-knowledge-infogr...
(and almost no complaints about London cabbies not knowing their way around!)