The road measures 16.38 miles long and would take a car obeying speed limits 22 minutes to travel its length.
The B4520 is a B Road and is located in the Zone 4 Highways Region.
This is a true long-distance route, journeying through numerous towns like BUILTH WELLS, Llandewir Cwm, Llangynog, Upper Chapel, Lower Chapel, Llandefaelog Fach, Pwllgloyw, Garthbrengy, and BRECON.
The road is located entirely within Powys.