Where are the wall section and the pillars from?
Wall section is entirely scratchbuilt from a 1" thick insulation foam piece (for the outerwall and side wall) and a 2" thick piece (for the inner). The arch is foam core. The stone look was gotten by scoring the foam with a pencil and then pressing a piece of stone into the foam to break up the smoothness. The ruined ends of each part were simply me attacking them with a hooked, sculpting tool. I then went in and cut some blocks out to complete the look.
The pillars are wedding cake toppers glued to a CD. One pillar was cut to make it look like the top had fallen off.