Stunning views of Milford Sound and Fiordlands National park in rainy weather, with countless waterfalls flowing down the sheer sides of the mountains. Milford Sound is a fiord in New Zealand’s South Island, in Fiordland National Park. It is considered one of the most beautiful fiords in New Zealand and in the World. Milford Sound is famous with its waterfalls, rainforests, steep slopes of the surrounding peaks and the classical views of Mitre Peak.