[Az-Geocaching] historical info on benchmarks

For those of you who have gone to Lonesome Bush cache and seen the benchmark there, I have a little information on the benchmarks in that area. This is courtesy of the Casa Grande Valley Historical Society.
 
"Local speculation states that these benchmarks were used for aerial surveys by the army when they would fly their U2 planes. The reason being was to synchronize their cameras for accuracy on reconnaissance missions."
 
They weren't sure of that information so I'm still trying to find out exactly why they were put there. If anyone is interested, I'll post any further information I find out. I won"t be spilling any military secrets.The army no longer uses that area. The benchmarks and concrete pads are in disrepair and most of the land is now privately owned.MSN 8 helps ELIMINATE E-MAIL VIRUSES. Get 2 months FREE*.