Hollyhock's "Cob House" on Cortes Island, B.C., Canada. This building is used as a spiritual retreat. Years ago I was present on many of the days it was being hand built. Cobb construction involves straw and mud and other hand worked innovations; glass bottles were placed through the walls during construction where ever through-wall holes were necessary for outlets or other needs.
Hollyhock is now a non-profit educational and healing retreat center; http://www.hollyhock.ca