Archaeological excavations at the site found human bones, fragments of silver clasps, bronze buckles and a knife. Archaeologists say the objects seem to date from between 1000 to 1200 AD.
Archaeological research at the site, which is set to be developed for the construction of a municipal heating network, will continue through mid-September.
Archaeologists were very surprised by the find, as they had believed the Tuukkala site had been thoroughly investigated.
An archaeological find was last made in the area in 1938.