I got tired of the hill washing down onto our driveway, so I decided to build a retaining wall. After looking at a number of concrete block options, I decided to build mine with stones and mortar. It is about 75 feet long, 1 foot thick, and varies from one foot tall on the high end to three feet tall on the low end by the garage. I got a 13 yard dump truck load of rock and about 80 bags of mortar. It took me approximately four months to finish the wall. I had a custom stone engraved and built that into the wall for future generations to laugh at.