I built a small L shaped block retaining wall about 5 courses high(bit less than a metre) and about 4 metres long in total. I've built a few in the past, and always dug large footings. But this time it was in an awkward spot, and having to lug concrete all that way would have been difficult, and the small area meant it was certainly not worth getting a concrete pump for it. Anyway, I only built the wall with very small footings(about 10cm deep by 30cm width with trench mesh and vertical rods...

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