Zimbabwe is a gemstone set in the middle of southern Africa, and it is largely occupied by a plateau, reaching its maximum altitude on the eastern side, along the border with Mozambique, while along the western side, it drops in the Kalahari sand. The capital city, Harare, is located at 1,490 m above sea level and experience a pleasant climate even in late summer. The country is an inland country, far from the ocean, but is crossed by some of the most important rivers of the African continent: the Limpopo river marks the border with South Africa, while the Zambezi river, the fourth longest river in Africa, marks the one with Zambia. In the north-east corner of Zimbabwe, the Zambezi falls for about one hundred meters into the legendary Victoria Falls, and further downstream it forms the large Kariba Lake, an artificial water basin originated by the construction of the Kariba dam-wall. Kariba Lake is actually a small inland sea, on which fishing and tourism are well developed. National Parks, conservation areas and private game reserves are numerous and many of them are joined to form one of the largest wildlife transfrontiers corridors in Africa. Zimbabwe counts five UNESCO sites, including the ruins of the ancient and mysterious city of Great Zimbabwe and the beautiful granite hills of Matobo.