Bir Tawil is a 2,060 km2 area of land along the border between Egypt and Sudan, which is uninhabited and claimed by neither country. When spoken of in association with the neighbouring Halaib Triangle, it is sometimes referred to as the Bir Tawil Triangle, despite the area's quadrilateral shape; the two "triangles" border at a quadripoint.

Its terra nullius status results from a discrepancy between the straight political boundary between Egypt and Sudan established in 1899, and the irregular administrative boundary established in 1902.

Egypt asserts the political boundary, and Sudan asserts the administrative boundary, with the result that the Hala'ib Triangle is claimed by both and Bir Tawil by neither. In 2014, author Alastair Bonnett described Bir Tawil as the only place on Earth that was habitable but was not claimed by any recognised government.

Bir Tawil is 2,060 km2 in size. The length of its northern and southern borders are 95 kilometres and 46 kilometres respectively; the length of its eastern and western borders are 26 kilometres and 49 kilometres respectively. In the north of the area is the mountain Jabal Tawil, with a height of 459 metres. In the east is Jebel Hagar ez Zarqa, with a height of 662 metres. In the south is the Wadi Tawil, also called Khawr Abū Bard.

Due to its status as de jure unclaimed territory, a number of individuals and organizations have attempted to claim Bir Tawil as a micronation. However, none have been taken seriously by the international community, and due to the remoteness and hostile climate of the region, the vast majority of these claims have been by declarations posted online from other locations. None of these claims, or any others, have been recognized, officially or otherwise, by any government or international organization.

According to en.wikipedia