Entry in progress—B.P.
   
Paleofuture
The “Highway of Light” That Guided Early Planes Across America
Matt Novak
11/18/13 11:08am
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Built by the U.S. government, the airmail beacons of the mid-1920s helped pilots find their way much more safely — whether it was day or night. Spaced out every few miles, from New York to San Francisco, each site consisted of a revolving motor-driven light which sat at the top of a 60-foot tower. The 1931 illustration above from the FAA archives shows how the light tower sat in between a concrete arrow on the ground and a building that contained a generator, which powered the entire thing.
 
Originally approved by Congress in 1921, the light beacon system was planned to cross the entire United States by mid-decade.
     
Walk Down the Lane 
EVER HEARD OF A LAND ARROW?
2015/06/17 JANET SEVER HULL
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These enormous, concrete arrows were 50 – 70 feet long and pointed west.  They stretched all the way across our country and were spaced roughly 10 miles apart and were painted a bright yellow to be easily visible from a distance of 10 miles or more.  Each arrow pointed the way to the next arrow in the route.
 
In the center of each land arrow was a 50 foot tall steel tower with a rotating gas or electric powered light.  A small shed was built on the tail of the arrow to house the generator and to give the keeper a place to rest.  All of these beacons were given a number which was painted on top of the generator shed.
 
In all, 700 land arrows were built in the 1920’s as part of the world’s first ground-based civilian navigation system to aid the air mail pilots in their cross country flights.
 
Contra Costa (CA) Times
Pointing the way to aviation’s past: Walnut Creek’s concrete arrows
By Sam Richards .(JavaScript must be enabled to view this email address)
POSTED:  01/03/2016 02:08:06 PM PST1
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It is a remnant of the Transcontinental Airway System, a network of about 1,550 concrete arrows built from 1924 to 1931 to help airmail pilots complete nighttime transcontinental flights faster than trains in an era before radar was practical in aviation. The arrows were accompanied by revolving beacons that replaced a ragtag collection of bonfires and burning oil drums. The project was initiated by the U.S. Postal Service and the U.S. Commerce Department’s Bureau of Air Commerce.
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The arrows, from 50 to 70 feet long and usually painted bright yellow for visibility, were about 10 miles apart on average, depending on whether the terrain was flat or mountainous. They guided open-cockpit biplane pilots along established routes on an 18,000-mile national mail-delivery network. The original route, from San Francisco to New York City, was nicknamed the “Highway of Light” and roughly followed the present-day path of Interstate 80, especially in the West.