Brussels and the European Union a provisional seat, though with the Common Assembly in Strasbourg as that was the only city with a large enough hemicycle (the one used by the Council of Europe). This agreement was temporary, and plans were set to relocate the institutions to Saarbrücken which would serve as a "European District", but this did not occur. The 1957 Treaties of Rome established two new communities, the European Economic Community (EEC) and the European Atomic Energy Community (Euratom). These shared the Assembly and Court of the ECSC but created two new sets of Councils and Commissions (equivalent to the ECSC's High Authority).
European Economic Community the European Economic Area covering 15 countries. Upon the entry into force of the Maastricht Treaty in 1993, the EEC was renamed the "European Community" to reflect that it covered a wider range than economic policy. This was also when the three European Communities, including the EC, were collectively made to constitute the first of the three pillars of the European Union, which the treaty also founded. The EC existed in this form until it was abolished by the 2009 Treaty of Lisbon, which incorporated the EC's institutions into the EU's wider framework and provided that the EU would "replace