On 2 May 2012, José Manuel Barroso, President of the EC, chaired the 2000th weekly meeting of the College of the EC. The first meeting of the EC took place on 06/07/1967, after the entry into force of the so called "Merger Treaty" (or "Brussels Treaty") on 01/07/1967. This Treaty created a single institutional structure, including the Commission as a single executive, for the European Communities. To mark this anniversary, an exhibition was shown from 27/04/2012 to 07/05/2012 on the ground floor (Piazza) of the Berlaymont building. It displayed the table of the College meetings in use in the late 1960s, a video recalling the various Colleges since 1958, a selection of pictures illustrating the history of the institution, and copies of the agenda and minutes of the College meetings number 1, 500, 1000 and 1500.