Bird, I'll have measure the thickness but I'd estimate 3/16 th " It's thicker than a 55 gal drum. The center door helps with cleanout and smaller boxes etc. the bottom burned out of my 55 gal so I laid it on it's side and fed brush from both sides. I was impressed how well that worked so I scaled it up and corralled the embers better
Hopefully with the thing on stilts, more surface area, less water inside and ventilation that'll slow the rust.I used an air chisel to cut out the doors. Very slick and incredibly noisy.
You'll notice two hooks high just off center to avoid the chimney for carting it around.