The photo shows remnants of stone filled double layer brick walls. The walls are built with river cobbles held together with argillaceous mortar.
okapi
cc-noncommercial-Attribution 3.0
Jean-Pierre Protzen
Jean-Pierre Protzen
02.12.2009
"10244.jpg." Tracing Tambo Colorado, Item #38 (accessed September 06 2010, 11:15 am)