This article is about the Class III road numbered C680 maintained by DfI Roads. For other roads numbered C680, see C680.
The C680 starts on the B50 near Mulnavar Lodge and heads north, soon crossing Fairy Water. The road north consists of many straight segments with only the occasional bend, eventually meeting the C672 south of Ardstraw. The road is crossed by itself at Letterbin with another segment of the route starting on the C679 near Lough Fanny and heading west. This segment soon turns northwards, crossing the River Derg and eventually meeting the B164. From here the road continues northwards for a short distance before terminating on the B72 at Dinacrum.