Flying in the 20s had to be a thrilling experience, indeed. In the absence of radio communication or radar technology, pilots engaged in American coast to coast airmail or passenger service had to rely on often imprecise navigation charts to avoid getting lost. Most of the time they were alone in the air, flying on desertic territory, hoping to reach the destination without encountering bad weather.
To help guiding the pilots across the impervious North American territory, the Congress funded the construction of very large arrow-shaped Airmail Beacons, (up to 20 meters in lenght). Every concrete arrow, painted in bright yellow, was accompanied by a 15 m tall tower, emitting a powerful gas powered light. Each arrow pointed towards the next, separated one with another by a distance of 3 to 10 miles. The beacon towers have been scrapped and recycled for WWII, while the yellow paint has since been worn off by the elements, but the enormous solid concrete arrows are likely to stand there for good.
April 1971, “Field-girdling fences of unmortared stone, built of rocks cleared from the land, create a gray maze on Inishman - Middle Island. The hundreds of miles of gateless walls that honeycomb Aran pastures and gardens shield the shallow soil from buffeting winds.” View this on the map