The road measures 9.52 miles long and would take a car obeying speed limits 17 minutes to travel its length.
The B721 is a B Road and is located in the Zone 7 Highways Region.
This is a true long-distance route, journeying through numerous towns like ANNAN, Howes, Dornock, Eastriggs, Rigg, and GRETNA.
The road is located entirely within Dumfries.