Lake Tanganyika is one of a series of geologically old lakes that have filled areas of the main East African Rift Valley. Look at a map of Africa and you will see many of these in a 'string' down the continent: Lakes Malawi, Tanganyika, Kivu, Edward and Albert are some of the larger ones. Zambia just has a small tip of Tanganyika within its borders, but it is of importance to the country. Access to Tanganyika grants Zambia a real port with transport links to a whole side of Tanzania and direct access to Burundi.
It also makes this one corner of Zambia totally different from the rest of the country, with a mix of peoples and a 'tropical Central Africa' feel. There are some well-established lakeside lodges, most within striking distance of Kalambo Falls, and two of the old lodges in the vicinity of Sumbu National Park are already emerging as the area's rising stars.