Originally it appears that the platform was mostly surrounded by log railings, with a single stone arch, as seen below...
I am not yet sure when the modern railings and renovations were put in place.
Photo Currently Unavailable
Detail: Constant and Dramatic Change Interpretive Sign (2015)Historic Columbia River Highway. Oregon. March 13, 2015Photo Currently Unavailable
Detail: Constant and Dramatic Change Interpretive Sign (2015)Historic Columbia River Highway. Oregon. March 13, 2015Photo Currently Unavailable
Detail: Constant and Dramatic Change Interpretive Sign (2015)Historic Columbia River Highway. Oregon. March 13, 2015