Possible bunker or other earthwork, Zaragoza side of the Mirador de las Tres Huegas hill
"... In the afternoon we did our first guard and Benjamin showed us round the position. In front of the parapet there ran a system of narrow trenches hewn out of the rock, with extremely primitive loopholes made of piles of limestone. There were twelve sentries, placed at various points in the trench and behind the inner parapet. In front of the trench was the barbed wire, and then the hillside slid down into a seemingly bottomless ravine; opposite were naked hills, in places mere cliffs of rock, all grey and wintry, with no life anywhere, not even a bird. I peered cautiously through a loophole, trying to find the Fascist trench.
‘Where are the enemy?’
Benjamin waved his hand expansively. ‘Over zere.’ (Benjamin spoke English — terrible English.)
‘But where?’
According to my ideas of trench warfare the Fascists would be fifty or a hundred yards away. I could see nothing — seemingly their trenches were very well concealed. Then with a shock of dismay I saw where Benjamin was pointing; on the opposite hill-top, beyond the ravine, seven hundred metres away at the very least, the tiny outline of a parapet and a red-and-yellow flag — the Fascist position. I was indescribably disappointed. ..."- Homage to Catalonia, Chapter 2
