🇩🇪 Berlin Ringbahn
🇧🇪 Brussels Line 2
🇧🇪 Charleroi Loop
🇺🇸 Chicago Loop
🇷🇺 Koltsevaya Line
🇬🇧 London Circle Line
🇪🇸 Madrid Line 6
🇪🇸 Madrid Line 12
🇺🇸 Miami Metromover
🇯🇵 Toei Ōedo Line
🇯🇵 Yamanote Line

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🇹🇭 Bangkok Blue Line
🇨🇳 Beijing Line 2
🇨🇳 Beijing Line 10
🇷🇺 Bolshaya Koltsevaya Line
🇷🇴 Bucharest Line M1
🇨🇳 Chengdu Line 7
🇧🇩 Chittagong Circular Railway
🇨🇳 Chongqing Loop Line
🇩🇰 Copenhagen Circle Line
🇮🇳 Delhi Pink Line
🇮🇳 Delhi Ring Railway
🏴󠁧󠁢󠁳󠁣󠁴󠁿 Glasgow Subway
🇨🇳 Guiyang Loop Line
🇨🇳 Guangzhou Line 11
🇩🇪 Hamburg U3
🇨🇳 Harbin Line 3
🇫🇮 Helsinki Ring Line
🇹🇼 Kaohsiung Circular Light Rail
🇹🇷 Kadıköy-Moda Nostalgia Tramway
🇵🇰 Karachi Circular Railway
🇮🇳 Kolkata Circular Railway
🇲🇾 Kuala Lumpur Circle Line
🇦🇺 Melbourne City Circle
🇷🇺 Moscow Central Circle
🇯🇵 Nagoya Meijō Line
🇯🇵 Osaka Loop Line
🇳🇴 Oslo Ring Line
🇫🇷 Paris Line 15 🚧
🇯🇵 Sapporo Streetcar
🇰🇷 Seoul Line 2
🇨🇳 Shanghai Line 4
🇸🇬 Singapore Circle Line
🇹🇼 Taipei Circular Line
🇭🇰 Tin Shui Wai Circular
🇯🇵 Toyama City Tram Line
🇲🇲 Yangon Circular Railway
🇨🇳 Zhengzhou Line 5