It made me think of myself as a bag of cells that leave behind a mineral deposit after several decades. The large concentrated piles of such "mineral deposits"

It made me think of myself as a bag of cells that leave behind a mineral deposit after several decades. The large concentrated piles of such "mineral deposits" in the catacombs prompted me to consider all the people who contributed (physically, intellectually, artistically) to building the great city throughout the centuries. Definitely a worthwhile visit!