Jansenville is a small Karoo town established in 1855 and named after Jan Willem Janssens, Governor of the Cape Colony in 1803.
Jansenville sits on the banks of the Sundays River. It is north of the Zuurberg Mountains in an area known as the Noorsveld, after a cactus-like succulent that is common in the district. Between Jansenville and the Zuurberg to the south is a plain that marks the northern boundary of the Addo National Park, while to the north are some hills which have a scenic drive and, at the summit, shortly before the descent through the Ratelskloof Pass, there are views across the Camdeboo plains to the peaks of the Sneeuberg.
Jansenville is game country and in the area there are game farms, hunting concessions, and nature reserves including the Addo Elephant National Park.
Jansenville is 167 km north west of Port Elizabeth on the R75. It is 84km south of Graaff-Reinet.
- Jansenville Fort (north of the town). It was erected by the British in 1901 during the Anglo-Boer War. It saw no action, but attests to the guerrilla activity in the area in that conflict.
- The restored Sid Fourie House serves as a museum.
- The town's notable buildings include the large Dutch Reformed Church, a building in the basilican style made of local stone which is a heritage site.