Newcastle is the third-largest city in the province of KwaZulu-Natal, South Africa. The city is KwaZulu-Natal's industrial centre. The majority of its citizens reside in Newcastle East in the main townships of Madadeni and Osizweni, with the balance residing in Newcastle West (the two sides of Newcastle are separated by the N11 Road). Set at the foothills of the northern KwaZulu-Natal Drakensberg Mountains, Newcastle is located in the northwest corner of the province along the Ncandu River.
Newcastle is the seat of the local municipality as well as being the seat to the Amajuba District Municipality. Newcastle's municipal area is 188 square kilometres (73 square miles), ranking Newcastle as South Africa's tenth-largest city, and consists of 31 wards.
The N11 and R34 are the principal roads linking the city to the rest of South Africa.