I'm looking at constructing something decorative on each side of our driveway culvert. I'd like to use retaining wall blocks and possibly either keep it capped with stone blocks on top or leave it open to fill with river rock or mulch. Any suggestions of how to do this and what supplies I all need? I wasn't sure if you'd need to fill the driveway "slopes" with dirt or soil first, use landscaping cloth, block puddy to hold the blocks together, etc? Has anyone done something like this and if so can you give me a run down of the steps you needed to do? Thanks!