New Zealand is comparable in size to the United Kingdom or the Philippines. Nowhere is more than 130km from the sea. Sitting on the Pacific Rim, New Zealand has earthquakes and volcanoes. The climate is generally temperate, although weather in the far north is often subtropical during the warmer months (December–March) and there can be severe frosts in the inland areas of the South Island in winter (June–August). New Zealand originally had no land mammals, but has many unique native plants and birds, such as the flightless kiwi.