Helvetica and the New York City Subway System

Here is an example of a work that leaves no stone unturned, and does the job properly. There is an excellent introduction on the historical signage of the Subway, a proper explanation of why a new wayfinding system was necessary, the most comprehensive history on why Unimark was chosen to improve the signage and all the images you need of how their 1970 'Graphics Standards Manual' was implemented. Shaw rightly explains the move from the Standard Medium typeface to Helvetica and why it superseded Standard Medium and the fate of the original Unimark system.