List of public transport routes numbered 4
# List of public transport routes numbered 4

In public transport, Route 4 may refer to:

* Route 4 (MTA Maryland), a bus route in the suburbs of Baltimore, Maryland
* Barcelona Metro line 4
* NWFB Route 4, a bus route in Hong Kong
* London Buses route 4
* Line 4 (Madrid Metro)
* Line 4 Yellow (Montreal Metro)
* 4 (New York City Subway service), a subway line in New York City
* Shanghai Metro Line 4
