Line 4
- 12.17x44mm
- 4 (Los Angeles Railway)
- 4 (New York City Subway service)
- 4 Line (Sound Transit)
- 4 Train (disambiguation)
- Barcelona Metro line 4
- Busan Metro Line 4
- Eastern Suburbs and Illawarra Line
- Line (unit)
- Line 4 (Athens Metro)
- Line 4 (Beijing Subway)
- Line 4 (Bucharest Metro)
- Line 4 (Budapest Metro)
- Line 4 (Changchun Rail Transit)
- Line 4 (Changsha Metro)
- Line 4 (Chengdu Metro)
- Line 4 (Chennai Metro)
- Line 4 (Chongqing Rail Transit)
- Line 4 (Dongguan Rail Transit)
- Line 4 (Fuzhou Metro)
- Line 4 (Guangzhou Metro)
- Line 4 (Hangzhou Metro)
- Line 4 (Hefei Metro)
- Line 4 (Kunming Metro)
- Line 4 (Madrid Metro)
- Line 4 (Metro Bilbao)
- Line 4 (Milan metro)
- Line 4 (Moscow Metro)
- Line 4 (Mumbai Metro)
- Line 4 (Nanchang Metro)
- Line 4 (Nanjing Metro)
- Line 4 (Nanning Metro)
- Line 4 (Ningbo Rail Transit)
- Line 4 (O-Train)
- Line 4 (Osaka)
- Line 4 (Qingdao Metro)
- Line 4 (Rio de Janeiro)
- Line 4 (Saint Petersburg Metro)
- Line 4 (Shanghai Metro)
- Line 4 (Shenzhen Metro)
- Line 4 (Suzhou Metro)
- Line 4 (São Paulo Metro)
- Line 4 (Tianjin Metro)
- Line 4 (Wuhan Metro)
- Line 4 (Wuxi Metro)
- Line 4 (Xi'an Metro)
- Line 4 (Zhengzhou Metro)
- Line 4 Sheppard
- Line 4 of the Guadalajara urban rail system
- MRT Line 4 (Metro Manila)
- Mexico City Metro Line 4
- Mexico City Metrobús Line 4
- No. 4 Line (Baltimore streetcar)
- Paris Métro Line 4
- Paris Tramway Line 4
- Rodalies Barcelona line 4
- Route 4 (Baltimore)
- Santiago Metro Line 4
- Santiago Metro Line 4A
- Seoul Subway Line 4
- Sri Petaling Line
- U4 (Vienna U-Bahn)
- Yellow Line (Kolkata Metro)
- Yellow Line (Montreal Metro)
- Zhonghe–Xinlu line