Fragments of glassy petrified grass and microscopic traces of plant material, dating to around 200,000 years ago, are all that’s left of a Paleolithic hunter-gatherer’s bed in the back of Border Cave.
https://arstechnica.com/science/2020/08/people-slept-on-comfy-grass-beds-200000-years-ago/
https://arstechnica.com/science/2020/08/people-slept-on-comfy-grass-beds-200000-years-ago/