When you stumble across one of these (roughly) 150 concrete arrows, they don’t look like much. Four rectangles and a triangle flush against the ground. Some are the size of a Cadillac. Some are the size of a school bus. Almost crumbling edges and surfaces cracked like alligator skin. This isn’t a result of shoddy workmanship—let’s see how you look after a century of elements batters you. 

Once upon a time, 1500 of these concrete arrows dashed across the United States, placed every 10 to 20 miles and connecting Chicago, Los Angeles, New York, Atlanta, San Francisco, and Las Vegas. 1500 arrows attached to 1500 beacons, traversing 18,000 miles of America,  collectively called the Transcontinental Airway System. A single arrow and beacon didn’t seem all that impressive. A concrete arrow painted canary yellow, connected to a 53-foot tower and a small generator shed, topped by a rotating beacon. The rotating beacon’s five million candlepower cut through clouds and fog for over a mile, although the same power can be snatched on Amazon for $40. 

These beacons weren’t just marvels, they were necessities. It’s easy to forget how immensely, unbelievably, astoundingly HUGE the continental United States actually is. Sure, countries like Russia, Canada, and China have more land, but how much of that land is inhabitable? According to the World Population Review, the United States has the largest amount of arable land in the world. That means our postal system has a lot of ground (and airspace) to cover, and airmail was the way to do it. 

Flying your way across the country in the days before reliable radio navigation (even rudimentary GPS navigation was a half century away) was risky business, particularly at night. Pilots had an easier time flying during the day, but that limited the efficiency of airmail. They had to fly, day AND night. In the 1920s, pilots found air route maps notoriously inaccurate. Major Reuben H. Fleet, an early airmail planner, had no faith in these maps. “There were no maps of value to airmen in those days. Official state maps of the region were all of different scales and showed only political divisions with nothing of a physical nature except cities, towns, rivers, etc.”

 

 

Flying by compass then just wasn’t precise enough, since the compasses were affected by the metal in the aircraft itself. That kind of dead reckoning navigation was aptly named, since a half-degree miss on a compass heading could mean fifty miles off course from much-needed fuel or an airstrip. The country needed a reliable, efficient method of guiding pilots along these routes both day and night. 

The beacons were the answer. During the day, pilots would mark the yellow-painted arrows, which pointed them to the next beacon and the next and the next, allowing them to leapfrog from city to city. At night, the beacons beamed. Modern aircraft would hardly note these bright lights from 30,000 feet, but in the 1920s, airmail pilots often stayed below a few thousand feet, sometimes as low as a few hundred feet. This wasn’t only for navigation and visibility. Those biplanes had open cockpits and the higher the altitude, the colder the temperature. At 30,000, the altitude of modern passenger jets, the temperature wavers around -50 ℉. The friendly skies are damn cold. 

The first route, built in 1923, covered the thousand mile stretch between Chicago and Cheyenne. Smack in the middle of the United States, this route allowed pilots leaving from either coast during the day to hit the 284 beacon stretch by nighttime. It worked. The US Air Mail established more cities and more routes. By 1933, 1500 beacons criss-crossed 18,000 miles of the country.

The system worked, but soon grew costly and obsolete. Improvements in radio and navigation technology made low-altitude beacons less useful. Wartime necessity meant salvaging the angle iron used in the beacons’ construction. Civil Defense decided that an extensive system of brightly colored concrete arrows, pointing directly to America’s major cities, would prove handy to enemy bombers. The arrows were painted over, covered, or simply dug up. 

 

It’s easy to take the speed and efficiency of our postal system for granted. We all complain about a letter that didn’t get here or a package delayted there, but statistically our postal system is remarkably effective. The majority of our mail arrives on time and in the right place. Today, computers and a network of carriers and regional hubs provide that service, but a century ago, it was a system of concrete arrows and mini-lighthouses, guiding cold pilots over the American landscape. 

 

 

 

Want to Know More?

Check out ‘The Blog at Denny G’s Road Trips’ which contains a wealth of info on the three remaining Indiana concrete arrows.  A great read and a labor of love. 

Discover a great resource at ‘Arrows Across America.’ Here you can find resources on concrete arrows and beacons across the entire United States. It also has the reported locations of former sites, so GPS sleuths can hunt on their own. Again, a couple dead links, but plenty of live ones.