Landscape in Vang ViengThe climate is tropical and monsoonal. There is a distinct rainy season from May to November, followed by a dry season from December to April. Local tradition holds that there are three seasons (rainy, cold and hot) as the latter two months of the climatologically defined dry season are noticeably hotter than the earlier four months. The capital and largest city of Laos is Vientiane, and other major cities include Luang Prabang, Savannakhet and Pakxe.

In 1993, the government set aside 21% of the nation's land area as National Biodiversity Conservation Areas (NBCA), which may be developed into a national park system.

Wikinews has related news: "Living fossil" found in LaosLaos is the home to the Indochinese tiger, the giant gaur, and the Asian elephant. A number of animal species have been discovered or re-discovered in Laos in recent years. These include the striped or Annamite rabbit, the saola, and most recently the Laotian rock rat or kha-nyou.

The country is one of four in the opium poppy growing region known as the "Golden Triangle". According to the October 2007 UNODC fact book "Opium Poppy Cultivation in South East Asia", the poppy cultivation area was 15 square kilometres (3,700 acres), down from 18 square kilometres (4,400 acres) in 2005.