Valuable archeological finds have been unearthed on two Olympics 2012 sites.
The Roman coin was buried beneath a river wall
Pottery from the 4th Century and a Roman coin were found on the London stadium site and Iron Age activity found on the Aquatics Centre site.
The finds will form part of the Museum of London's collection but digging activity will not delay building work, the games' organisers say.
Archeological work to date the items and place them in historical context will now take place.
The first Londoners lived in thatched circular mud huts on the site that will house the Aquatics Centre, but in the Iron Age would have been a small area of dry land in a valley of lakes, rivers and marshes, archeologists believe.
Early Londoners lived by and fished in what is now the River Lea and parts of the pots they would have used to cook their fish have also been discovered.
The Aquatics Centre will be beside the river which is currently being widened by 8 metres, as part of a programme to restore the ancient waterways of the Lower Lea Valley.
The Roman Coin and pottery were found buried behind a wooden river wall that may have been built and used by the Romans.
Olympic Delivery Authority Chief Executive David Higgins said: "We are taking this opportunity to tell the fascinating story of the lower Lea Valley before it is given a new lease of life for the Games and future generations.
"It is a story of change and transformation dating back centuries.
"The archaeological work has been long planned in conjunction with our programme and will not cause any delays."