1959 Amsterdam Arlington Australia 1960 Austria Belgium Berlin Bern 1961 Bishkek Bosnia and Herzegovina Brussels 1962 Bucharest California Cambridge Canada 1964 Canberra Croatia 1965 Czech Republic Dubrovnik Edinburgh Estonia Florence 1967 Florida France Germany Gold Coast Great Lakes Groton 1968 Gulf Shores Hamburg Heidelberg India Indianapolis Indonesia 1970 Italy Kingston Kyrgistan Lake Geneva 1973 Latvia Lisbon Lucerne Malta Monterey Munich 1976 Netherlands New Delhi New London New York Norway 1977 Oklahoma City Orange Beach Oslo Ottawa 1980 Paris Pensacola Porto Portugal Prague 1981 Riga Romania 1982 Rotterdam Russia Saint Petersburg San Antonio San Diego Sarajevo Seoul 1985 Singapore Sliema South Korea South Kuta 1989 Split Stockholm Sweden Switzerland Sydney Tallinn 2006 Tartu Texas Toronto United Kingdom Ulm USA Vienna Washington DC Waukegan Williamsburg