Maybe consider Sandstone Estates near Ficksburg
(NNW of and near Lesotho border
(where LROC are going Sept this year ... )
... a well established Agricultural Estate and Transport Collection etc with many activities ...
I have not been there but seems a good family base
with access to many events and places incl trails
... see website and Wicki entry at end of this note.
... also, of special interest: 4 offroad trail routes nearby:
Old Mill 4x4 Route
A magnificent off-road drive as you follow the northern bank of the Caledon River in an easterly direction before ascending the mountain. This route is recommended for the more seasoned enthusiast and in places might require engagement of low range. Gradients vary, but in instances can be as steep as 1:4. Note that this route is furthest from Sandstone and takes the longest to complete. There are only two departures (14 vehicles per group) and you will not be able to do another route on the same day. The route takes 7-8 hours to complete.
Camelroc 4x4 Route
A challenging drive for the more adventurous, found just outside of Fouriesburg. Situated right on the border between South Africa and Lesotho, the Camelroc Guest Farm offers a challenging 4x4 route. The route takes about 3 hours to complete and 6 vehicles per group are allowed.
Lesoba 4x4 Route
Lesoba Guest Farm, which is situated 13kms outside of Fouriesburg, offers a fun self-drive 4x4 route on the farm which meanders through breath-takingly beautiful scenery between the Free State and Lesotho. The route takes about 3 hours to complete and 10 vehicles per group are allowed.
Wynford River 4x4 Route
The route follows the police patrol road which traces the Caledon River, starting at Wyndford Guest Farm ending at Union House. The route winds its way along in a South Westerly direction offering views of magnificent sandstone cliffs. The route has some tricky sections, but it is a fairly easy drive. Only 10 vehicles per group will be allowed. The route takes 2,5-3 hours to complete."
https://www.sandstone-estates.com/
https://en.wikipedia.org/wiki/Sandstone_Estates
... Famous Fiver VoorLoper ...
... Veni Vidi Vici ...