Ethiopia hosts 80% of Africa's highest mountains, a legacy of the region's volcanic past. 30 million years ago, a huge plug of molten volcanic rock welled up through cracks in the Earth's crust, then cooled and solidified to form the Ethiopian Highlands. Since then, erosion has carved the edges of this rocky dome to spectacular effect. And there is a surprise up here. In this arid land, a lake. At nearly 2,000 metres, Tana is Africa's highest. Tana's hippos live at a higher elevation than any other. Could Lake Tana be the elusive source of the Nile's great flood? The mere trickle flowing out of it doesn't look promising. But the rocks here tell a different story. Only a raging torrent could have carved these shapes.


非洲80%的崇山峻岭坐落在埃塞俄比亚境内，它们是这块土地上昔日火山传奇的遗迹。三千万年前，熔融状的大量火山岩从地壳的裂隙中涌出，冷却之后凝固成了埃塞俄比亚高原。从那时起，蚀刻作用在这块圆顶状巨石上雕刻出了雄伟壮观的景致。这高原之上还有着一个令人惊喜的发现。这块不毛之地上竟然有座湖泊！海拔高度将近两千米，塔纳湖是非洲最高的湖。塔纳湖河马的栖息地高居世界之冠。塔纳湖会是尼罗河泛滥的神秘源头吗？从塔纳湖流出的细流看来，这种可能性并不大。但岩石们却诉说着不同的故事。只有狂暴的洪流才能蚀刻出这样的景观。