access to the Johannesburg CBD in the west and the Germiston CBD in the east. Next, the N3/N12 heads to Bedfordview, where the N12 leaves the N3 at the George Bizos Interchange (previously known as the Gillooly's Interchange; just east of the Eastgate Shopping Centre), joins the R24 Highway eastwards and provides access to the East Rand and O. R. Tambo International Airport. This interchange with the R24 is purported to be the busiest interchange in the Southern Hemisphere. From here, the N3 continues going northwards as the Johannesburg Eastern Bypass and bypasses Edenvale and Alexandra before terminating at the Buccleuch Interchange just south of Midrand and north of Sandton, which is the point at which the N3, N1 and M1 converge. Alternative route Where the N3 has been realigned, the old alignment has been designated R103. The R103 exists in three sections: between Durban and Ladysmith, between Warden and Villiers, and between Heidelberg and Johannesburg. The only exception is within Durban itself, where most of the old N3 alignment is designated as the M13 instead of having the usual R103 designation; the R103 diverges from the M13 in Gillitts just outside Durban. The R103 is typically used to avoid the toll plazas on the N3, with one notable exception being the Tugela East Toll Plaza located on the R103 itself where the R103 and N3 meet north of Ladysmith. Prior to the redesignation of the National Route numbers in 1971, the N3 moved east at Heidelberg and passed through the towns of Standerton, Volksrust and Newcastle via Laing's Nek Pass, before joining the present alignment at Ladysmith. This route now designated R23 between Heidelberg and Volksrust and N11 thereafter to Ladysmith remains an alternative to the N3. Dual carriageway sections Following the opening of the motorway section in December 2001 between Heidelberg and Villiers, the N3 now has at least two lanes in each direction for its entire length between Johannesburg and Durban. The section between Johannesburg and Villiers is dual carriageway motorway. Between Villiers and Warden the road is single carriageway motorway with two lanes in each direction. From Warden to Keeversfontein (Tugela Toll Plaza; Ladysmith) the road is no longer motorway but retains two lanes in each direction. Thereafter, the route to Durban is dual carriageway motorway. This last section from Ladysmith to Durban is the second longest motorway by route number (after the N1 between the