Australia and New Zealand 15N is a fifteen-night trip that starts in Sydney, moves to New Zealand's North Island, then covers the South Island's alpine country and Queenstown. It suits travellers who want two countries in one holiday and are happy with several long travel days. The package is land-only, so international flights are booked separately.
The Australian leg is three nights in Sydney, which gives time to settle before the flight to Auckland. In New Zealand, the route spends two nights each in Auckland, Rotorua and Christchurch, then one night each in Taupō, Wellington, Aoraki/Mount Cook and Te Anau, and two nights in Queenstown. Milford Sound is a full day from Te Anau.
Check the Australian entry requirements separately, because they differ from New Zealand's. The package includes visa assistance and private transfers on arrival and departure. Read the New Zealand travel guide for background on the islands, or see New Zealand tour packages for a New Zealand-only trip.