The well-preserved remains of a wooden structure that is no less than 476,000 years old, pre-dating the appearance of Homo sapiens by 100,000, have been discovered at Kalambo Falls in Zambia. Two logs were found in an interlocking position, joined by an intentionally cut notch. Early hominins whittled, shaped and stacked timbers into an unidentified structure that may have been a shelter, a raised track, a fishing platform or something else entirely.
That's really, really old. And it's wood, not stone.