Did you know that there are giant concrete arrows all in a line across the country?
In the early 1900s, air travel wasn’t what it is now (or even what it would become in 30 years). It was dangerous, and primitive, and slow. But it was still the fastest way to get mail from New York to San Francisco. So after WW2, the surplus air planes that survived, and the pilots that flew them took up jobs with the US Postal Service flying mail across the country. This was before the times of Google Maps, before every kid had a globe in their class room, or even a well detailed map of the state they were in. It was hard, bordering on impossible to fly in an accurate route across the country.
So, the US government installed giant concrete arrows along with 5 story light house lookout towers along the main air mail routes. The towers were visible for miles around, and helped guide the pilots along the thousands of miles of flying they had to do.
With the advent of radio in the 1940s, and then the jet age, and commercial planes flying more and more, these became less necessary. Actually, most of the towers were dismantled and used for scrap for the WW2 War effort. But the arrows themselves are still in the ground in some places, and you can follow them if you choose.
I wonder now, in 2,000 years if America is no more, what the future inhabitants of the land will think of these arrows. They will be America’s Stonehenge, no one will know for sure, but lots of theories.