Interzonal Tournaments

The crucial qualifying stage of the World Championship cycle from 1948 to 1993. Winners and top finishers earned spots in the Candidates Tournament, one step from challenging for the World Championship.

How It Worked

Zonal Tournaments → National and regional qualifiers feeding into the Interzonal

Interzonal Tournament → Top 20-24 players compete, top finishers qualify for Candidates

Candidates Tournament → Winner earns a World Championship match

From 1973, multiple Interzonals were held per cycle. From 1990, Swiss system replaced round-robin. Replaced by Chess World Cup from 2005.

1948🇸🇪Saltsjobaden🇷🇺 Bronstein20-player round-robin1952🇸🇪Saltsjobaden🇷🇺 Kotov21-player round-robin1955🇸🇪Gothenburg🇷🇺🇨🇿🇦🇷🇭🇺🇷🇺🇷🇺 Bronstein, Pachman, Pilnik, Szabo, Spassky, Geller21-player round-robin1958🇷🇸Portoroz🇱🇻 Tal21-player round-robin1962🇸🇪Stockholm🇺🇸 Fischer23-player round-robin1964🇳🇱Amsterdam🇷🇺 Smyslov24-player round-robin1967🇹🇳Sousse🇩🇰 Larsen23-player round-robin1970🇪🇸Palma de Mallorca🇺🇸 Fischer24-player round-robin1973🇧🇷Petropolis🇧🇷 Mecking18-player round-robin (Interzonal A)1973🇷🇺Leningrad🇷🇺 Karpov18-player round-robin (Interzonal B)1976🇵🇭Manila🇧🇷 Henrique Mecking20-player round-robin (Interzonal A)1976🇨🇭Biel🇩🇰 Bent Larsen20-player round-robin (Interzonal B)1979🇧🇷Rio de Janeiro🇭🇺 Portisch18-player round-robin (Interzonal A)1979🇷🇺Riga🇱🇻 Tal18-player round-robin (Interzonal B)1982🇪🇸Las Palmas🇭🇺 Zoltan Ribli14-player round-robin (Interzonal 1)1982🇲🇽Toluca🇭🇺 Portisch14-player round-robin (Interzonal 2)1982🇷🇺Moscow🇷🇺 Kasparov14-player round-robin (Interzonal 3)1985🇨🇭Biel🇷🇺 Vaganian16-player round-robin (Interzonal 1)1985🇲🇽Taxco🇳🇱 Jan Timman16-player round-robin (Interzonal 2)1985🇨🇺Havana🇷🇺 Sokolov16-player round-robin (Interzonal 3)1987🇦🇺Sydney🇬🇧🇬🇧 Short, Speelman16-player round-robin (Interzonal 1)1987🇷🇺Uzhgorod🇷🇺 Yusupov16-player round-robin (Interzonal 2)1987🇭🇺Szirak🇷🇺🇺🇦 Ehlvest, Ivanchuk16-player round-robin (Interzonal 3)1990🇵🇭Manila🇧🇾🇺🇦🇷🇺 Gelfand, Ivanchuk, Salov64-player Swiss1993🇨🇭Biel🇮🇱 Gelfand73-player Swiss (FIDE)1993🇳🇱Groningen🇬🇧 Michael Adams54-player Swiss (PCA)

Legacy

The Interzonal system produced some of the most dramatic tournaments in chess history. Fischer's dominance at the 1970 Palma Interzonal (18.5/23), the 6-way tie at Gothenburg 1955, and Kasparov's debut at Moscow 1982 all happened at the Interzonal stage. Since 2005, the Chess World Cup has filled a similar role in qualifying players for the Candidates.