A catalog of maps, large or small, is a treasure trove of information. A collection that when sitting static is still always growing and always changing. Everyday its value as a temporal benchmark of human growth and innovation increases. The map itself is a snapshot of place and data (or at least a window into the mind of the cartographer) at any given moment in time, but over time the assembling of maps can unveil an incredible subject matter timeline. Alot of cartographers and collectors have commented on this and, in fact, celebrated this.  Personally, I find historical road atlases to be particularly of note in cartographic historic analysis, and one of my favorite days of the year is when the newest annual Rand McNally road atlas is released. In the past I’ve spent hours, days, probably weeks, poring over each page, comparing new to old, observing the changes and progress of the past year. New highways completed, routes renamed, new stadiums, air force bases repurposed to civilian use, two lane roads upgraded to large expressways.

These Rand McNally atlases I speak of have changed over the years, both through design and layout (worth a whole other post in itself), but there are certain consistencies from page to page that have lasted through the years. The consistencies provide the potential for a fascinating qualitative and quantitative temporal analysis of urban progress and growth. What features come onto the map over the years? What fall off? What infrastructure is important, what is superseded?

I began by locating the newest and oldest atlases I had in my library from the annual Rand McNally series. The oldest that would work was the 1986 edition, with a nice Rodeway truck emblazoned on the cover, and the newest (that wasn’t all wrinkled up out in my car) was the 2011. They just happened to sit a quarter century from each other, perfect. With the two subject maps identified, I had to pick a subject area and outline the criteria to do so.  The most important of the criteria, the selected map extent and design style had to be largely unchanged from 1986 to 2011. Many stylistic and scale differences were implemented over the years, so the mapped extent had to be at about the same detail throughout. And finally, the mapped extent had to be a region of extensive urban growth, with many new communities, growing infrastructure, and new points of interest, such as shopping malls and airports.

The subject winner: the massive metroplex of San Bernardino, Ontario, and Riverside in the beautiful San Bernardino Valley in Southern California, known colloquially as the “Inland Empire”. After some edge matching, layer mashing, georeferencing, and a small bit of rubber sheeting… the pictorial results.

This first snapshot is of San Bernardino and the immediate vicinity.  Notable changes include the establishment of San Bernardino International Airport on the old Norton Air Force Base grounds, and the massive growth and establishment of community assets (ballparks, shopping centers, civic centers) near the large interchange at Interstate 10 and Interstate 215.  Also noticeable is the completion of the CA-210 Loop around the north and east of the city.  Population of San Bernardino in 1986: 140,000 – Population of San Bernardino in 2011: 205,000

This second snapshot is Moreno Valley, California, or simply known as Sunnymead in 1986.  This is one of the most extreme examples of urban growth and suburban sprawl in the entire United States during this time.  Moreno Valley was incorporated in 1984, and grew by 70,000 people in the 1980s alone.  The arterial roads remain the same, but quite noticeable are the upgrade of Interstate 215 to freeway standards and the establishment of many community resources, parks, hospitals and centers. Population of Moreno Valley in 1986: 40,000 – Population of Moreno Valley in 2011: 195,000

A third snapshot focuses on the Interstate 15 freeway corridor.  Notable is the establishment of Interstate 15 south of Mira Loma, and superseding of Temp 15 (Hamner Avenue) along that stretch.

Any conclusions or theories drawn are clearly illustrative, but the exploration in itself is engaging and revealing.  A more thorough time series over the 25 year period, maybe a snapshot every two years, would be a fascinating addition, and reveal individual years of rapid growth, precise establishment of points of interest and civic features, and interesting regions of urban expansion (or lack thereof).

Of course, I only picked out three notable areas among many, the growth of the entire region is remarkable. Explore the map yourself!

(A Graphicarto/Mapbox/QGIS Creation)

Happy Mapping,

-Mike

PS I highly encourage anyone to go lose themselves for a day in David Rumsey’s vast historical collection, you won’t regret it.