Country diary: In these stones lie clues to the past

Cressbrook Dale, Derbyshire: One drystone slab bears remnants of marine life from 300m years ago

The hill called Hay Cop at this national nature reserve commands spectacular views southwards across Derbyshire. So I forgive myself for not initially noticing the two limestone slabs standing upright in a dismantled wall.

This drystone structure is being rebuilt and these two columns, 1.2 metres high, perhaps 35cm apart, have been left to serve presumably as the stile through which walkers will pass. The stones were probably first cut when there was no such thing as engine noise here and the loudest human sounds were the clank of hammer on metal as a thick L-shaped iron bar was driven into the heart of one rock as a gate hinge.

Next to this detail is snagged a long, whitish, wind-wittering strand of wool, and it occurs to me that this one hair has a heritage stretching back probably to the Zagros mountains of Iran, where sheep began their 11,000-year journey of domestication to this very spot.

On the other stone, however, is the evidence of a deeper past. The surface limestone ripples with fossils of crinoids or sea lilies, echinoderm animals anchored by a central rope-like stem into the seabed and possessed of swaying seaweedy limbs that sifted out planktonic food from the currents when this place was an ocean more than 300m years ago.

The beautiful crinoid remnants take me to another time, but there is one detail here that carries me into another galaxy. Around the old gate hinge is a tarnished grey metal mass, used to secure the blacksmith’s ironwork and probably extracted from these very hillsides, given that lead mining here dates back to the Romans.

Yet lead originates through stellar nucleosynthesis in the hearts of stars called supernovae, whose explosions have scattered the rare element across space, until it finally came to rest at the birth of our solar system about five billion years ago. Lead was veined through the underworld of this landscape and then fixed as solder around this hinge. So, walker, when you pass this spot next, recall that you are seeing the one place, but you are brushing past a whole universe.

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