The presidents of Botswana, Zambia and Zimbabwe have signed a deal to build a bridge linking the three countries across the Zambezi River.
The project, expected to cost $70m, has been under consideration since 1999.
Boundary difficulties have prevented previous attempts to build the bridge, but during talks in Harare, leaders agreed to lay these aside.
The bridge at Kazungula will take the most direct route possible, crossing islands in the middle of the river.
The Kazungula crossing, upstream from the Victoria Falls, has been an important trading link since the 19th century, when colonial powers sought access to the Zambezi.
The borders of four countries - Botswana, Zambia, Zimbabwe and Namibia - converge there.
The Kazungula border crossing is currently served by a vehicle ferry, which capsized three years ago, killing at least 15 people.
Political borders have long been economic barriers in Africa and growth has always been hampered by poor infrastructure, BBC southern Africa correspondent Peter Biles says.
It is hoped that the Kazungula Bridge will open up this regional trade route between southern Africa and countries to the north.