A double grave with the imprints of flowers has provided the oldest proof of flowers decorating gravesites. The flowers that decorated the grave of a couple in Israel are 13,700 years old.

The graves are located in a cave on northern Israel's Mount Carmel. Sweetly scented flowering plants, such as mint and sage, were imprinted into the soft mud around the graves.

A new study shows that the adult pair had flowers lining their gravesite. Imprints of the stems and blossoms still survive. The grave was from the Natufian culture, which was prominent in  an area that is now Israel, Jordan, Lebanon, and Syria between 15,000 and 11,600 years ago.

Four graves were lined with flowers. The most notable grave holds the bodies of two people. They are an adult male and an adolescent whose sex has not been determined.

The "Pagan burial altar", as the gravesite has also been called, belonged to the Natufians society. They  were the first society to use graveyards, and they may have also been the first culture to transition from nomadic hunter-gatherers to permanently settled tribes.

The Natufians were likely the first to honor their dead with flowers. There was pollen found on an older site, but it may be coincidental or due to rodents.

"From [the Neanderthal] example until the Natufians", which was a 50,000 year-a period, "there is not one example [of flowers decorating graves]," said study leader Nadel.

The graves were prepared with care. A pit was dug, then lined with a thin laquer of mud. The bottom was filled with lavender and pink plants in bloom. The sweet-smelling flowers were chosen for their strong fragrances. Thus, the pair was buried ceremonially.

"They didn't just place the bodies inside the graves and leave," he said. "We have to envision a colorful ceremony that maybe included dancing, singing, and eating. They may have hunted a few animals and had a big meal around the graves and then threw bones or meat inside," Nadel said

"There are hundreds of flowers on Mount Carmel during the spring, but only a small group provide very strong fragrances. It's impossible that the Natufians didn't recognize the smell," he added.

Researchers are working to identify the relationship, age, and gender of the recently-found people in the flower-lined graves.