In Current World Archaeology 63 (www.world-archaeology.com) … we learn the Buddha was born in an era prior to writing so the story relies on an oral tradition. The earliest temples, made of stone and brick, date to the end of the 3rd century BC, after Indian emperor Asoka promoted the religion of Buddhism and created a stone column at Lumbini. The site of Lumbini is in modern Nepal and by tradtion this is the birthplace of the Buddha. Archaeologists, led by Robin Conyngham of Durham University, and Kosh Prascal Acharya of Nepal have unearthed an early brick structure at the Maya Devi Temple in Lumbini (provisionally dated to the time of Asoka), and beneath it, a wooden temple of the same design that has been dated by its timbers to the 6th century BC, confirming the oral tradition. Tree roots exist in a central unroofed area – perhaps the tree at the heart of the Buddha story.
In the same issue there is an article on Neolithic China – which continued to the end of the 3rd millennium BC. In what is known as the Middle/Late Longshan period (Neolithic) to Early Xia (Early Bronze and probably early 2nd millennium BC, surviving until the advent of Shang, around 1600BC. A large city of this Late Neolithic phase has been found at the confluence of two tributaries of the Yellow River covering an area of 400ha – which is quite impressive in size for the time. It is in fact the largest site of the period found in China to date, and interestingly, a pyramid shaped structure with a surrounding wall ten storeys high has been found. It was roughly contemporary with the pyramids of Egypt.