The 135-meter-long (443 foot) boundary between Botswana and Zambia is the shortest land boundary in the world. The Botswana–Zambia border connects two tripoints on the Zambezi River, one with Namibia in the northwest to one with Zimbabwe in the southeast. This incredibly short land boundary on the Zambezi River is also known as the quadripoint area. The double tripoints were made while the nations were under colonial rule, and while all four of the other boundaries received official delimitations, the Botswana–Zambia frontier has never been formally agreed upon. Botswana and Zambia have not revisited their boundary delimitation since independence, and the two States maintain good political relations.