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This is my latest terrain piece for my tabletop games, a small gorge. It's about 300 x 150 mm, and at its deepest the gorge is about 30 mm deep.
It's not wide enough for vehicles in any scale larger than 6mm or 10-12mm. Maybe a jeep in 15mm, certainly nothing larger. There's just enough of a bend in it that you can't see right through from end to end.
I suspect that the rock formations would make geologists clench their fists and grind their teeth, but fortunately, I'm not a geologist.
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