Village in the Willem Pretorius Game Reserve near the Sand River, 30 km from Winburg. The name is derived from the Allemanskraal dam, some 9 km to the North-West. The Sand River Convention was signed there in 1852, which gave independence to the South African Republic.

Geolocation
27° 1' 48", -28° 9' 36"
References

New Dictionary of South African Place Names by Peter E. Raper.

https://www.linx.co.za/tripreports/allemanskraaldam/index.php