Once home, I investigated further into what this arrow was doing on top of a fairly remote mountain top. With a few hours of searching, I came across information that sounded just like what I found onto of Tussey Mountain. Before GPS and modern navigation methods, huge markers were placed on the ground for the Transcontinental Air Mail service. These markers provided a route for planes to follow during the day and even at night. During the night many markers had control sheds and towers with lights to help guide the planes. In 1920, the first United States coast-to-coast Air route was developed and by 1929 beacons and markers spotted the ground about every 10 miles. Only a few beacon houses and towers still exist. Many were dismantled during war times for their steel and when they became obsolete to modern navigation. More of the concrete arrows still survive but are slowly being taken over by mother nature.
The arrow on Tussey Mountain was once part of Los Angeles to New York Airway on the Ebensburg to Philadelphia branch. To reach the arrow, Take Mountain Road east from Williamsburg, PA. From the opposite side, take Route 26 aka Raystown Road South of Huntingdon and just north of Marklesburg to reach Mountain Road.