The road measures 14.73 miles long and would take a car obeying speed limits 21 minutes to travel its length.
The A821 is a A Road and is located in the Zone 8 Highways Region.
This is a true long-distance route, journeying through numerous towns like Trossachs, Aberfoyle, CALLANDER, Brig O'Turk, and Kilmahog.
The road is located entirely within Stirling and Falkirk.