The N3 is a national route in South Africa that connects Johannesburg and Durban, respectively South Africa's largest and third-largest cities. Johannesburg is the financial and commercial heartland of South Africa, while Durban is South Africa's key port and one of the busiest ports in the Southern Hemisphere and is also a holiday destination. Durban is the port through which Johannesburg imports and exports most of its goods. As a result, the N3 is a very busy highway and has a high volume of traffic.