I've been collecting used cement blocks for 40 years or more and have lost very few over the years to breakage. I must have about 400 or so at this point, most in 3 stacks in various places on the property.
They hold up extremely well in contact with the soil and provide for good air circulation under the stack.
Yes, I am a fan of using recycled cement blocks for stacking firewood. They are really not that difficult to move and I do move a few out of the way for stacking in the back of the woodshed. The dimension of my wood shed doesn't allow for much of a gap left at the end of the blocks but easily a couple of inches can be gained by leaving a gap between blocks. I also like that the 8 inch width of the blocks can support the ends of two rows of firewood. I make sure of course that the bottom of the rows of firewood that the wood is long enough to span the gap between rows of blocks but once the base is started shorter pieces can be easily stacked and 'odd chunks' can be dropped between rows and do not find their way to the ground.
I'm like a preacher that won't shut up about blocks for stacking firewood!
Sorry about that, and the bragging.
A couple of more photos. Each of the 8ft X 8ft bays hold about 3 plus cords stacking to over 6ft high sometimes.
Stack of extra blocks.
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Blocks moved for stacking in the rear of the woodshed:
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Woodshed from a distance:
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