|Location Map ( geo)|
|Distance:||23.5 km (14.6 miles)|
|Meets:||R390, R389, R446, R436|
The R391 runs from the R390 at Habsborough, 5 km west of Mullingar in County Westmeath, to the R436 at Lehinch, 2 km east of Clara in County Offaly. Most through traffic between Mullingar and Clara would be more likely, however, to use the higher-standard N52 to reach the R436 westbound.