Archaeologists have found the world's oldest mattress in a cave in South Africa:
The mattress—which consists of layers of reeds and rushes—was discovered at the bottom of a pile of bedding made from compacted grasses and leafy plants. The bedding had accumulated at the Sibudu Cave site in KwaZulu-Natal (map) over a period of 39,000 years, with the oldest mats dating to 77,000 years ago. [...]
What's more, researchers believe the ancient people added a "top sheet" to the bedding made of insect-repelling greenery, possibly to ward off biting bugs such as mosquitoes and flies.
The whole family slept on it: Link