Looking for Iron Age locations

The dry summer days show off structures ordinarily not visible at ground level, or even like this from the air when all is well watered at other seasons and even during the summer of a typical rainfall year. Here are a few structures in the vicinity of Eire's giant New Grange stone building of millennia ago, https://www.flickr.com/photos/mythicalireland/41635425520/in/explore-2018-07-16/

No doubt these will contribute to the mapped locations and finds across the hilltops through the British Isles around the time that implements and weapons of iron overtook the weaker points of bronze (admixing copper with tin) and before that the artifacts of copper alone.

New henge discovery near Newgrange I was at the centre of a major archaeological discovery in the Boyne Valley last week. Using a drone, I found a massive crop mark which is believed to be the footprint of a huge late Neolithic henge or enclosure. I was flying with Ken Williams at the time. The markings are only visible because of the prolonged drought in the area.

dry weather reveals subsurface structures (aerial view; drone uses)

Low tide lines in the long-term water cycle, as well as droughts bring opportunities for Space Archaeologists and aerial spotting of human activity in places normally obscured by water tideline or surface vegetation. Here are examples of crop marks in the fields around Wales:

Cropmarks 2018 (Royal Commission on the Ancient and Historical Monuments of Wales)