Looks Great Jeff. Did you use mortar between the blocks? I think your right,..... the blocks will last longer. I think you're right to cap those corners. I doubt they can climb up the face of the blocks but they may try. How high is the enclosure?
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Vichris
"The object of life is not to be on the side of the majority but to escape finding oneself in the ranks of the insane"- Marcus Aurelius