The B5385 is a link road in west Northamptonshire. It gained its number when a previously unclassified road was given Class II status in the 1930s.
The road turns off the A428 to the west of East Haddon and heads west, soon reaching Long Buckby. The village name is apt as it takes some time to reach the village centre. Here we bear left, then there's a badly signed TOTSO right (the unclassified road ahead leads to the station and Long Buckby Wharf). Continuing west we zigzag through village streets narrower than before but then widens again. There's a sharp left-hand bend on the edge of the village then we go under the Northampton Loop Line and bear right again.
The railway line is followed briefly before we bear off to the left. On the near side of the village of Watford we give way at a triangular junction. Originally the B5385 ended here on the B4036 but that road was removed from the area in the 1990s so the B5385 TOTSOs left and takes on that road's old route. We head west then south through Watford before heading southwest again across open country.
It's not long before we cross the M1 just north of Watford Gap services, with back exits to the service station joining our road either side of the bridge. In quick succession we then go over the Grand Union Canal and the West Coast Main Line by the site of the now-gone Welton station (Welton village is some distance away but the station was presumably not named Watford to avoid confusion with the town in Hertfordshire). After passing a couple of warehouses the road ends at a crossroads on the A5; the ex-B4036 ahead is now unclassified.