The 80-strong team have dug up thousands of pieces of pottery and flint dating back to 6,000 BC.
They've unearthed pits where meat was cooked by hunter gathers during the Middle Stone Age, when the land was covered in forests.
They can tell that by the Iron Age -700BC to 43AD) a small village had appeared.
Many of the objects are already on display at the Museum of London.
Eventually, the new airport building will cover the site.