But when 43-year-old Tanja Hols decided to open the wooden chest she was stunned to find a bounty of gold and silver coins that had been left there for more than 200 years. 

Experts think that the box of coins from ancient Rome, Greece, and the Byzantine Empire could be worth "millions," according to Chris Parsons at the Daily Mail. 

The forgotten treasure had been sitting on the fourth-floor archive, overlooked by past library workers for centuries.