#1 Only Grand Slam to have been played in 2 countries

The Australian Open is not just the only Grand Slam to have been held twice in the same year (1977), it also holds the unique record of having been held at the most locations - 7 different cities including two different countries (Australia and New Zealand).
Sydney has played host on 14 occasions, Adelaide on 17 occasions, Brisbane in 7 different years, and Perth on 3 occasions. Christchurch and Hastings, both in New Zealand, were the hosts in 1906 and 1912 respectively.
Since 1972, the venue has been Melbourne. From 1972 to 1987, the tournament was played at the Kooyong Lawn Tennis Club. In 1988, the tournament moved to Melbourne Park and along with that, a change of surface from grass to hard courts were also effected. With extensive renovation activities being carried out by the Government of Victoria, it looks unlikely that the Australian Open will be moved again any time in the near future.
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