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 "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. José Manuel Barroso received Albert II, King of the Belgians, to visit the exhibition.