Last week I visited Underground Maps Unravelled, an exhibition entirely devoted to underground diagrammatic maps, and particularly presenting an in-depth analysis of the London Underground Diagram (LUD). Dr. Maxwell Roberts explores information design alternatives of the very first LUD created by Henry Beck in 1933.
In addition to a historic evolution of the LUD, Roberts goes further and presents his own versions of the LUD. Each of them explores a different variable of the original set of design principles employed in the LUD. Roberts’s work demonstrates that to obtain successful and effective results it is necessary something more than the merely application of a bunch of design principles.
The key is that design principles have to be purposely applied, and designers have to know how to apply them and why they are applying them in order to create an effective diagrammatic map. Roberts explains that one of the parameters to measure the effectiveness of a network diagrammatic map is according to number of ‘elbows’ that composes the route of a (tube) line. The more quantity of elbows a line has, the more broken it is, and the more difficult to be followed by readers and users. In order words, a map is more effective when the route of its lines is easily followed, and thus understood. As an example, Robert experiments changing the angle of the straight lines, and increases the number of intersections. However, this changes are not arbitrary, his work systematically breaks Beck’s rules searching for a more effective version of the LUD. Different versions of the LUD can be seen at the exhibition.
One of the most interesting diagrammatic maps of Roberts’s work is a LUD created by fragments of previous versions of the LUD (see image below). This version of the LUD permits to appreciate and understand the visual evolution of the LUD and how its elements have changed.
More transport diagrammatic maps complements the exhibition, such as diagrammatic maps from Berlin, Paris and Madrid underground transport networks.

Fourth space of the exhibition, where underground diagrams from Paris, Madrid and Berlin can be seen.
Roberts has also included some ‘aesthetic maps’ where the application of design principles relies on a second level, as the objective of these maps is different, more related to beauty than to functionalism.
The exhibition runs until September 24, at The Minories Gallery, in Colchester. And for those who prefer to wait until next month or would like to see it twice, you can visit the exhibition next October from the 7 to the 22 at Scott Brownrigg, in London.