July 10, 2021

Gridded Roads on the Midwest

I think we’re all familiar with grid plans in cities. Streets and avenues. But outside cities? I remember what seemed to be to be far out of town “5 Mile Rd” and “10 Mile Rd” as a kid in Boise, ID. But, I never quite thought long and seemingly endless numbered and gridded roads were common in the country. They seemed like a town thing.

This summer we drove across the USA - East to West to East over six weeks. One day we drove from Minneapolis, MD to Sioux Falls, SD and I noticed that there were roads like “501st Ave” intersecting our little highway a couple hours West of Minneapolis, the numbers steadily increasing as we drove further out of the city. I thought “We don’t have those in NC!” It got me thinking about how these might differ around the country. I resolved to do some exploratory mapping when I got a moment.

I’ve been home a few weeks, and had a few spare hours to explore these ‘alphanumeric’ roads in Minnesota and other states around the country. There are several kinds of ‘alphanumeric’ road patterns: 15th St, NW 31st Ave, Avenue Q of course, Fourth St. I downloaded some census map data, and created some maps in R.

Other Places and thoughts

I generated several other maps: North Dakota, South Dakota, Illinois, Missouri, California, District of Columbia, Wisconsin, North Carolina, Florida.

Patterns I notice:

I’d probably have to read many books like From Footpaths to Freeways(history of MN roads) to arrive at a clear idea of how these roads came to be the way that they are.

© Dane Summers 2021