|From:||Bóthar na dTreabh / Seán Mulvoy Road, Galway (M301262)|
|To:||Galway city centre (M297256)|
|Length:||0.8 km (0.5 miles)|
|Meets:||N6, R338, R863|
The R866 is a short urban road in Galway. It links the N6 (Bóthar na dTreabh) / R338 (Seán Mulvoy Road) junction in the northern part of the city to the R863 a short way east of the Salmon Weir Bridge in the city centre. The main features along the road are shopping centres and supermarkets in the north, and narrow suburban houses in south.