street, around the corner of chestnut or francisco. >> these walls are common throughout the city, and they were built as part of the stimulus package following the great depression. it is known as the noriega wall, the leavenworth wall. they were well engineered. at that time, because of the depression, they really gave 100% to the work they were doing. even today, these walls, there is very little movement in these walls, they are performing well. you can check them against earthquake loads, there are more than adequate to resist any earthquake load that you can throw at them. i applaud the results of that stimulus package. >> this particular slide illustrates a bunch of things. one, the hill seemed beyond going down after the lower roadway, goes down quite steeply to pastry -- to bay street and soon thereafter hits the point where there is artificial fill. so you can see dramatically the naturally occurring landforms and the filled terrace. this was also interesting in that you can see alcatraz and angel island at beyond, which of course are the natural peaks of the underground mountains in the bay. so this slide wraps up a lot of conditions. >> is this back on the docks? >> no, these wa