The R51 is a provincial route in South Africa that connects Bapsfontein with the N3 north of Villiers, via Springs, Nigel and Balfour.

As Pretoria Road, it heads south-south-west for 10 km up to Petit (east of Kempton Park and north-east of Benoni), where it meets the M44 metropolitan route and continues by way of a left turn to become Geldenhuys Street southwards.

Just after the N12 Crossing (by Kingsway), the R51 is joined by the R29 route from Benoni Central and they are one road southwards for 5 km before splitting in the vicinity of Springs (the R29 becomes 4th Avenue eastwards).

[1] From Springs, the R51 crosses the N17 highway and makes a 20 km journey south to Nigel.

From Balfour, The R51 makes a southward 40 km journey, passing Grootvlei and its power station, making a left turn, to end at the N3 Johannesburg-Durban Highway (In Mpumalanga, just north of the Vaal River, which separates it from the town of Villiers in the Free State Province on the other side).