ICCA ranking. Barcelona has become the world’s top city in terms of attracting most congress delegates. The capital of Catalonia received 122,877 delegates at 179 conferences last year, according to the International Congress and Convention Association (ICCA). A test of the city’s strength in the competitive conference segment is the fact that since 2001, Barcelona is the only city in the world that has stayed in the top five cities with most conferences held each year. In the last decade (2004-2013), it has become the world’s second best city in number of congress participants (926,111), below Vienna (935,156), above Paris (878,948). ICCA statistics include international conferences that have a minimum of 50 participants and that regularly rotate between at least three different countries. The latter is important: Barcelona has positioned itself in the top position of the ICCA ranking without including events like the Mobile World Congress and its 80,000 delegates, which is only held in the Catalan capital.