Some believe that Stonehenge (2500 BCE) in England was built to help establish when the Summer Solstice occurred.
Males and Females sleep up to 18-20 hours a day in most cases. Depending on how hot or if the weather is perfect than the lion will sleep. If the weather is good ther will sleep about 14-18 hours and go hunting or playing.
Kittens are usually considered to be adults when they're around 12 months in age. Although adult cats usually don't sleep as much as kittens, they too can boast pretty impressive shut-eye hours. Normal mature cats that are fit as a fiddle often sleep for between 13 and 18 hours daily.