On a bluff south of Medicine Bow, Wyoming is the remains of this aviation arrow located at the seemingly forgotten airport.  Before our current GPS satellite & radar, airplane pilots who did transcontinental airmail routes at night would fly following these large cement arrows built high up on ridges or mountaintops, often accompanied by beacons with a light.  While there were over 1500 of them across the country back in the day, about 100 of them remain today, decaying & forgotten like this one.  This one was the 32nd arrow of the San Francisco - Chicago airway route which was officiated in September 1920 & lasted for several years until radar came.  Pilots would follow the beacons & directions of the arrows using a compass to stay aligned w/ each arrow until they encountered the next one, directing them ultimately to Chicago.  This particular arrow points in the direction towards the next arrow near the town of Bosler.  Most of these sites are now gone, particularly during WWII as a means of making sure any enemy aircraft didn't use these features to scout out American soil.  This site is unique in that all three components of the airway beacon are still intact, of which still include the beacon, arrow, & old generator shed, of which the latter two are seen directly below.  Maybe one day this will be kept in historical preservation before the Wyoming wind blows it all down.  The arrow is still relatively intact w/ a few cracks & the shed still stands, though there is aviation trash inside & the rooftop is missing the old painted numbers & letters.