Ian and Others,

You made another important point when you said they were made without
documentation. I have observed several cast concrete underground igloos that
served as field barracks, storage, and a morgue. There are probably lots more
out there. I also know of sandbagged trenches, wood-framed rooms, and cast
concrete bunkers that were also not marked on maps. In fact, the western
portion of Fort Rosecrans is honeycombed with unmapped trenches with igloos.
Personally, I feel these ought to be completely recorded and some should be
excavated.

Ron May
Legacy 106, Inc.