You wouldn’t know the Lion Pit was there. This overgrown gorge exists quietly, without the sensation its name implies, below a housing estate, by Lakeside shopping centre and within earshot of the M25, wedged on all sides as tightly as the newbuilds that line its cliffs. This is industrial West Thurrock, far south Essex, where the wild marshes that still thrive on the Blackwater Estuary, where I live in the north-east of the county, have long since disappeared.
As I arrive, a fox strolls up the road, urbanely cool. It darts over the edge and into the gorge. I follow it. Descend into the pit, and you’re down in deep time. Ice age time, to be precise, because this location has produced some of the most important archaeological finds of Britain’s Palaeolithic past.
The gorge is, in fact, a Victorian tramway, originally built to transport chalk, but the excavation revealed a superb section of ice age sedimentation. Little of this shows now, but there are glimpses still, high up on the slopes, beneath the thick undergrowth. I scramble up and touch the Pleistocene, reaching back over 200,000 years.
These deposits have been giving up their long-held treasures for over a century, revealing the megafauna that once roamed this Thameside site in Neanderthal Britain: bison, bear, mammoth, elephant. In fact, Neanderthals were right here, beneath the still-existing chalk cliffs, fashioning stone tools and butchering a woolly rhinoceros (a pelvis with cut marks was found). We know all this because, remarkably, their own debris is here too, buried in the sediment: flint flakes, struck from their lithic industries and left where they fell hundreds of thousands of years ago.
I can’t escape the mess of modern humans down here either. A shopping trolley, a mattress, a row of beer cans upended on twigs like makeshift decorations, a carpet of waste, ivied and brambled by more recent time.
This morning, wonderfully, is true winter: flint-sharp cold and a crystalline sky as clear and blue as glaciers. The pit’s detritus, old and new, is covered for a short time with a thick frost. Over the way, a lake below the chalk is solid ice. An ice age day for ice age adventures.
• Under the Changing Skies: The Best of the Guardian’s Country Diary, 2018-2024 is published by Guardian Faber; order at guardianbookshop.com and get a 15% discount
