The harbour's main population centre is Lyttelton, which serves the main port to the nearby city of Christchurch, linked with Christchurch by the single-track Lyttelton rail tunnel (opened 1867), a two lane road tunnel (opened 1964) and two roads over the Port Hills. Diamond Harbour lies to the south and the Māori village of Rāpaki to the west.
Lyttelton acts as the main population center for the harbour, supporting the port near Christchurch. The connection between these locations includes a single-track rail tunnel (opened in 1867), a two-lane road tunnel (opened in 1964), and two roads over the Port Hills. Diamond Harbour is to the south, and Rāpaki is west of the harbour.