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 Communities EEC was to create a customs union and general economic co-operation. It later led to the creation of a European single market. The EEC became the European Community pillar of the EU, with the ECSC and EAEC continuing in a similar subordinate position, existing separately in a legal sense but governed by the institutions of the EU as if they were its own. The ECSC's treaty had a 50-year limit and thus expired in 2002, all its activities are now absorbed into the European Community. The EAEC had no such limit and thus continues to exist. Due to the sensitive