Lyttelton is a port town on the north shore of Lyttelton Harbour / Whakaraupō, at the northwestern end of Banks Peninsula and close to Christchurch, on the eastern coast of the South Island of New Zealand.

Lyttelton Harbour / Whakaraupō is a major inlet on the northwest side of Banks Peninsula, on the coast of Canterbury, New Zealand; the other major inlet is Akaroa Harbour, which enters from the southern side of the peninsula. Whakaraupō enters from the northern coast of the peninsula, heading in a predominantly westerly direction for approximately 15 km (9.3 mi) from its mouth to the aptly-named Head of the Bay near Teddington. The harbour sits in an eroded caldera of the ancient Banks Peninsula Volcano, the steep sides of which form the Port Hills on its northern shore.