Dennis McClendon


Historical Maps: Rail Transit in North America, 1984 by Dennis McClendon

I thought I was all done with “to scale” maps of North American rail systems, but then Dennis McClendon (see previous posts from him) sent in this beautiful series of maps that he produced for Planning magazine back in 1984. I’ve split his double-page spread up into two separate images so that they can be viewed in better detail on Tumblr. Dennis himself says:

Given this week’s Tumblr theme, I thought you might be interested in these maps that I did in 1984, when I worked for Planning magazine. The “new wave” of modern light rail systems was just getting started. My initial idea was to do them all at the same scale, but integrating them with the text into a two-page magazine layout eventually required a compromise of doing them at two distinctive scales.

No GIS or even Illustrator in those days: I created these using Rubylith and Chartpak flexible line tape.

Of note is the large number of systems that were either brand new or still under construction: Portland’s “Banfield” line – now the main section of line between downtown and Gateway – being especially noticeable to me. Also – massive extensions under construction for the Washington DC Metro, and the parlous state of streetcars in New Orleans, with service on the historical St. Charles line only.

And just to throw further fuel onto the fire regarding the categorization of certain systems as either light rail or streetcar, which many commenters on Matt Johnson’s map brought up. In 1984 at least: Pittsburgh and Boston’s Green Line were classified as “light rail” while Philadelphia and the San Francisco Muni were seen as “streetcar”. Make of that what you will.

Source: Dennis McClendon via email.

Submission - Historical Map: Chicago CTA Rapid Transit Map, 1983

Submitted by our resident repository of Chicago transit map knowledge, Dennis McClendon, who says:

This map of Chicago’s rapid transit network originated in the 1970s (this one is from June 1983), and this style was used until routes received color names in 1993. Happily, by that time digital printing in fiberglass-embedded signs made full-color maps easier to place in graffiti-prone environments.

These maps were silk-screened onto [blue] color blanks, and every color of ink added cost. So the CTA’s six lines are represented by using only two colors. Simple black is used for three “extension” lines that never overlap. A simple white line is used for the north-south line those connect with. For the two other through routes: black with white casing and white with black casing.

The side ticks for stations work fine, but a box for the places where transfers are possible is not altogether intuitive.  The CTA of that era employed skip-stop spacing, so alternate trains stopped at A or B stations only. Another graphic decision that might have deserved more thought:  the names of various suburbs—only a few of which can be reached by rapid transit—floating in their vague geographic positions, but no indication of Chicago city limits or Lake Michigan.


Transit Maps says:

I have to say that I actually really like the forced graphic simplicity of this map. There’s only two colours to work with, so every element has to be very carefully considered and balanced against others for the map to work at all. That it manages to keep the route lines recognisable and separated in the downtown Loop area without the use of an inset map is quite an achievement.

The famous “A-B” stopping patterns are shown pretty deftly as well, being mostly placed on the opposite side of the route line from the station name. The few stations where this doesn’t happen (due to crowding or space limitations) stand out like a sore thumb – Jarvis on the North-South line, and many of the stations on the Ravenswood line. There are also two stations with their labels set at an angle: Merchandise Mart is almost completely unavoidable, but Harvard on the Englewood Line could easily have been fitted in horizontally.

I think the “boxed” interchanges work well enough, having seen similar devices on quite a few maps (the Paris Metro included) now. I also like the extra detail included on the map: station closures on weekends and nights, direction of travel around the Loop, inbound boarding only on the last three stations on the Jackson Park North-South Line, and more.

I would agree with Dennis on the locality names, that just seem to float in space. The biggest offender is “Evergreen Park”, right at the very bottom of the map, below the legend!

As for depicting Lake Michigan, that seems like a good idea, but I struggle to think of a way of doing it without upsetting the delicate balance of the map. You can’t really use a white line, as that could be confused with all the white route lines, and you can’t have a large white area as that would be visually way too heavy. In the end, the lake isn’t that important for such a graphically stylised map (it really just delineates the eastern side of the map), so I’m not too upset by its absence.

Our rating: A fine historical example of how to use a limited colour palette effectively. Minimalist but still effective. Three-and-a-half stars.

External image


Submission - Historical Map: Chicago Regional Transportation Authority, 1977

Submitted by Dennis McClendon, who has previously submitted material related to transit mapping in Chicago that I’ve featured on the site.

This map is a real beauty, and I definitely appreciate Dennis’ ability to talk about the technical aspects of cartography in the days before computers. We take computer-aided design almost completely for granted today – but map-making was a laborious, manually performed task back then, where a scalpel, a light box and rubylith film were vital parts of a cartographer’s arsenal.

I’m just old enough as a designer to have come in at the very end of this manual era of printing. My very first task in a real design studio was to cut up 48 pasteboards to mount the artwork for 24 double-sided leaflets on. I then marked up each and every board on an overlay with the colour specs for every element and instructions for stripping in photos from colour transparencies, or “trannies” (yes, really):

Tranny X - enlarge to 143%, crop as shown. Strip to keyline, delete keyline.

For every photo on every page.

But enough reminiscing about the olden days: on to Dennis’ thoughts on this fantastic map:


Because I’m hard at work on its modern successor, I thought you might be interested in a very curious and striking printed map from the 1970s: the famous black Chicago RTA map, first published in 1977.

This was the Chicago area’s first full-color transit map, a splashy beginning for the newly created Regional Transportation Authority that voters had approved to take over the region’s failing transit agencies and private companies. The colors used for the Chicago Transit Authority rail lines would—mostly by happenstance—be chosen 20 years later as the actual names for those lines (brown got swapped with purple for the line serving Northwestern University, whose school colors are purple and white).  Transit history geeks will understand the A and B symbols on the rapid transit stations as relating to Chicago’s skip-stop service (ended in 1995) during which alternating trains stopped only at A or B stations.

The system map exhibits several traits long associated with Chicago transit maps, such as the curving corners, dots at terminals, and bare route numbers next to the lines.  There are reminders of the era, like the Souvenir Bold Italic typeface used for points of interest.  The map was designed by Rand McNally, and the folklore is that they were hungry for the work. The same oil crisis that had boosted interest in public transit had made free gas station maps unnecessary, and that was a big part of Rand’s business. But the main design question is: why black? Printing a rich black generally requires two passes, or at least an underlayer of cyan.

The official explanation for the black is that it was a clever way to deal with misregistration of thin colored lines.  Undoubtedly there’s a lot of truth in that.  In those days of Scribecoat and photomechanical production, cartographers had to worry a lot about trapping and misregistration. So a close look at the thin blue and tan bus lines will reveal that a one point line has been photographically “spread” into a 1.4 point line that is behind a 1 point gap in the black (black is printed last in four-color printing). The method wasn’t always totally successful, and there are tiny white gaps around some of the point-of-interest names.  But an ordinary 1 point tan line would have been difficult to print, since it would be composed of a 20 percent dot each of cyan and magenta, and a 30 percent dot of yellow—all of which would need to line up exactly.  None of the colors would so dominate that the other colors could be “choked” to a narrower line that wouldn’t peek out.

Some of the printing details can be seen in the enlargement.  The rich black seems to be 100% black over 40% cyan.  The ocher-olive (not the most pleasing color, even in the earth-tone 1970s) looks to be about 60% black over 60% yellow.  A similar combination of cyan and black produces a handsome steely blue for the downtown inset.

A very curious design feature is that bus lines are never allowed to intersect.  Instead one line is always broken where another crosses it. Some of this was worked out by folks who knew the system well, and buses on overpasses, or buses making a 90-degree turn, are always shown on top of crossing lines. The others were randomized like a basket weave. The reason for this design choice isn’t obvious to me; it may be that it reinforces where lines turn a corner and where they continue straight. There doesn’t seem to have been a production rationale: at least one perfect uninterrupted crossing (Kimball and Peterson) is shown, apparently by mistake. The idea of color-coding bus lines by which rapid transit line they feed wasn’t a success.  Lots of crosstown lines reach four different lines along their lengths, and many crosstown bus riders aren’t headed to a rapid transit line at all.

But back to the main question, why black?  I never saw another example anywhere of a black transit map—except for Métro inset maps on Montreal’s maps in the 1980s, which were so obviously reproduced directly from the artwork used for panels inside the cars that they even include the warning not to interfere with the functioning of the doors.

I think the real reason was marketing. The RTA was a new agency that saw the value of graphic design to tie together the region’s disparate transit assets and build public support for them.  The maps, the signage typefaces, even the livery on locomotive, railcars, and buses was what we would today call “branding.” So while there may have been a good production justification for the striking black RTA map, I think the bigger reason was how cool it looked. Indeed, I had a copy hanging on my wall when I was in grad school a thousand miles away, never dreaming that 30 years later I’d be the designer trusted to make a new RTA system map useful and attractive.


Video: Making Vitreous Enamel Wayfinding Signage

As an aside to the last post about the 1983 Chicago CTA map, Dennis also sent along this fun little “How It’s Made” video about the process used to create signs such as this.

In the case of the CTA signs, the background blue would be the second layer applied to the steel signboard, and white and black would be the two screen printed colours that are then fired and fused permanently to the backing. It’s a time- and labour-intensive way of making signs (largely replaced by full-colour digital printing today) but it’s absolutely fascinating to see the process involved.