In 1899 Britain and Egypt decided in their agreement about the future of Sudan that the border between Egypt and Sudan lies on the 22nd parallel North. However in a few years it became apparent that some tribes are constantly crossing the border to reach some of their traditional grazing lands, so a new agreement was made in 1902 adapting the border. The new agreement assigned some area to the south of the 22nd parallel to Egypt as it was a grazing land of the Egyptian Ababda tribe; this area would become later known as Bir Tawil. Also, some lands to the North of the parallel were assigned to Sudan and those became known as the Hala'ib triangle. However the Hala'ib triangle is about ten times bigger than Bir Tawil, has a sea access and is generally deemed to be much more valuable and Egypt never let it go, especially since the British were not really interested in the matter. So when Sudan became independent it supported the 1902 border, claiming Hala'ib and giving Bir Tawil to Egypt. Egypt however never stopped claiming the border of 1899, claiming Halaib and leaving Bir Tawil to Sudan. So that way the paradox was born - by claiming Bir Tawil each of the two nations will relinquish its claim to Hala'ib, which both are determined not to do.
Currently both areas are under Egyptian administration. It is not really clear whether the tribes still visit the place and what is the exact border situation, since there is no road going there.
Coordinates:21° 52′ 14″ N, 33° 44′ 14″ E
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