Enclosures

I'm learning about archaeological surveying and the interpretation of aerial photographs. At the moment I think I understand it. The latest assignment will test that. I enjoyed the reading for last week, An archaeologist's guide to classification of cropmarks and soilmarks by Jonathan Edis, David MacLeod & Robert Bewley (Antiquity 63 (1989) 112-26): it features a good number of diagrams and drawings, the most pleasing being the following three, illustrating types of enclosure.