Archaeologists working in Nepal say they've uncovered evidence of the world's earliest Buddhist shrine linking the life of the Buddha to a specific century. A structure unearthed at the sacred Maya Devi Temple at Lumbini, Nepal -- a UNESCO World Heritage site long identified as the birthplace of the Buddha -- has been dated to the 6th century B.C. The timber structure, found beneath a series of newer brick temples, contains an open space in the center that links to the nativity story of the Buddha himself, the National Geographic Society reported Monday. Previously the earliest archaeological evidence of Buddhist structures at Lumbini dated no earlier than the third century B.C., the time of the patronage of the Emperor Asoka, who promoted the spread of Buddhism from present-day Afghanistan to Bangladesh. "Very little is known about the life of the Buddha, except through textual sources and oral tradition," said archaeologist Robin Coningham of Britain's Durham University. Some scholars, he said, believe the Buddha was born in the third century B.C. "We thought 'why not go back to archaeology to try to answer some of the questions about his birth?' Now, for the first time, we have an archaeological sequence at Lumbini that shows a building there as early as the sixth century B.C.," Coningham said. Long overgrown in the jungles of Nepal, the ancient site was rediscovered in 1896 and identified as the birthplace of the Buddha by the presence of a third-century B.C. sandstone pillar bearing an inscription documenting a visit by Emperor Asoka to the site of the Buddha's birth as well as the site's name -- Lumbini.