The best national parks in Tanzania include the iconic Serengeti National Park for the Great Migration, the Ngorongoro Conservation Area for its unique crater ecosystem, Lake Manyara National Park for tree-climbing lions, and Tarangire National Park known for its large elephant herds and baobab trees. For chimpanzee trekking, Gombe Stream and Mahale Mountains National Park are exceptional, while Mount Kilimanjaro National Park is essential for trekkers.