Not long ago, List Universe published a list featuring the 10 most densely populated countries or territories worldwide. For comparison, here are the 10 countries or territories with the least population density. (Note: different sources may report slightly varying figures, leading to some discrepancies.)
10. Mauritania

Population: 3,068,742; Area: 1,025,520 km²; Density: 3.0 people/km²
Mauritania, officially known as the Islamic Republic of Mauritania, is a country in northwest Africa. It is bordered by the Atlantic Ocean to the west, Senegal to the southwest, Mali to the southeast and east, Algeria to the northeast, and the Morocco-controlled Western Sahara to the northwest. In an area about the size of Ontario or Egypt, there are just 3 million people and not much else.
9. Iceland

Population: 309,672; Area: 103,000 km²; Density: 3.0 people/km²
The Republic of Iceland is an island nation in Northern Europe, situated in the North Atlantic Ocean between mainland Europe and Greenland. In an area about the size of Kentucky or the former East Germany, there are 300,000 residents and a lot of geezers (or perhaps geysers).
8. Suriname

Population: 449,238; Area: 163,820 km²; Density: 2.7 people/km²
Suriname, officially known as the Republic of Suriname, is located in the northern part of South America. It is bordered by Guyana to the west, Brazil to the south, French Guiana to the east, and the Atlantic Ocean to the north. Spanning an area roughly the size of Wisconsin or Tunisia, Suriname has a population of 450,000 people and is a melting pot of languages that may outnumber those spoken in any comparable nation.
7. Australia

Population: 21,050,000; Area: 7,682,300 km²; Density: 2.6 people/km²
The Commonwealth of Australia is a country located between the Indian and Pacific Oceans. It spans an area roughly the size of the contiguous 48 states of the USA or nearly twice the size of the European Union. With a population of 21 million, it is home to the world’s most venomous snakes. Two-thirds of the population resides in five major coastal cities, though very few snakes do.
6. Namibia

Population: 2,031,252; Area: 824,292 km²; Density: 2.5 people/km²
The Republic of Namibia is a country located in southwest Africa, bordered by the Atlantic Ocean to the west, South Africa to the south, Botswana to the east, and Angola to the north. With a population of 2 million people and an area roughly the size of Ontario or Pakistan, Namibia faces a significant challenge with HIV/AIDS.
5. French Guiana France

Population: 187,056; Area: 90,000 km²; Density: 2.1 people/km²
French Guiana (La Region Guyane) is an overseas department of France located on the northern coast of South America. It is bordered by Suriname to the west, Brazil to the southwest, and the Atlantic Ocean to the north. Like other overseas departments, French Guiana is also a region of France, one of its 26 regions, and an integral part of the French Republic. With an area roughly the size of Maine or Portugal, it is home to 187,000 people and the spaceport used by the European Space Agency.
4. Mongolia

Population: 2,646,487; Area: 1,564,116 km²; Density: 1.7 people/km²
Mongol Uls is a landlocked country situated between Russia and China in Central/East Asia. It is the world’s second-largest landlocked country (after Kazakhstan) and the least densely populated independent country. Covering an area roughly the size of Quebec or Iran, Mongolia has a population of 2.6 million people and boasts the world’s smallest stock exchange.
3. Greenland Denmark

Population: 56,916; Area: 2,175,600 km²; Density: 0.026 people/km²
Greenland (Grønland / Kalaallit Nunaat) is an ice-covered island located between the Arctic and Atlantic Oceans, northeast of Canada. As the world’s largest island, Greenland is a self-governing province of Denmark. Though geographically part of North America, it is politically and historically tied to Europe, specifically Iceland, Norway, and Denmark. In an area larger than Alaska and roughly the size of Saudi Arabia, it is home to 57,000 people and contains 2.85 million cubic kilometers of ice.
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2. Falkland Islands United Kingdom

Population: 3,060; Area: 12,173 km²; Density: 0.25 people/km²
The Falkland Islands consist of two main islands and 776 smaller islands located in the South Atlantic Ocean, 480 km off the coast of Argentina. A self-governing Overseas Territory of the United Kingdom, the islands have been claimed by Argentina since the British re-establishment of rule in 1833. With an area comparable to Connecticut or Northern Ireland, the islands are home to 3,000 residents and 583,000 sheep.
1. Western Sahara Morocco

Population: 440,000; Area: 266,000 km²; Density: 1.3 people/km²
Western Sahara is a disputed territory in North Africa, bordered by Morocco to the north, Algeria to the northeast, Mauritania to the east and south, and the Atlantic Ocean to the west. The Kingdom of Morocco and the Polisario Front independence movement (which governs the Sahrawi Arab Democratic Republic) both claim control over the region. In an area roughly the size of Colorado or New Zealand, the territory has a population of 440,000 people, vast deserts, and scarce water resources.