EU treaties: inside European archives in Brussels
19 April 2013 Last updated at 13:37 BST
Dozens of European treaties have been written and signed in the last 60 years with copies stored in huge boxes in Brussels,
Adam Fleming spoke to Philip Evans, Head of Agreements Office, who holds a ringside seat to European history at the signing of the formal documents,
They opened the boxes in a strong room which hold the paperwork stretching back to the 1951 Treaty of Paris, which set up the former European Coal and Steel Community.