Meru National Park (Kenya): Experiencing a massive renaissance after poachers decimated animal numbers and waged all-out war on park wardens, Meru is not only a beautiful reserve where you can spot the Big Five among increasingly good numbers of plains game and slightly rarer animals, but because it was virtually off-limits for so many years, it's seen relatively little development and consequently draws few visitors. Such alluring potential solitude is unlikely to last, though, so make this a priority if you'd like to get a glimpse of African wilderness before the developers step in.
Mafia Marine Park (Mafia Island): Lapping the largely uninhabited archipelago that lies 200km (124 miles) south of Zanzibar, Mafia Marine Park's waters hold some of the richest reefs in the world, with more than 400 species of fish flitting along its shallow reefs and plummeting walls, including the whale shark, found in the shallow waters on the northwestern side of the island, facing Kilondoni. With a grand total of six accommodation options in the entire archipelago, diving these clear waters is also a pretty exclusive experience.
Serengeti National Park (Tanzania, Northern Circuit): The Serengeti is the greatest game park on the continent. It's not just the wildlife (the sight of more than two million animals moving across the plains is quite a sight), nor is it the actual size (almost that of a small country), but rather the expansive views you find at every turn. It was the Maasai who called it Siringitu -- "the place where the land moves on forever" -- and it is precisely this sense of vastness that will blow you away: the sheer expanse of the short-grass plains like a yellow sea, broken only by occasional rocky outcrops and elegant acacia trees. And above it all, always the high noble arc of the African sky.
Tarangire National Park (Northern Circuit): While the focus for most travelers to Tanzania is nearby Serengeti, many come away claiming lesser-known Tarangire as the real highlight of their trip. It can't compete in terms of size, but it is a beautiful park, typified by century-old baobabs that stand sentinel above the open grass plains and riverbeds, and home to a vast array of animal and bird species, attracted by the permanently flowing waters of the Tarangire River. In fact, given its dense concentrations of animals -- second only to Ngorongoro -- there is every chance you will enjoy a higher incidence of sightings here than in Serengeti; elephants, in particular, are common.
Kilimanjaro National Park (Tanzania): Kilimanjaro is unique in the pantheon of great mountains, in that it can be scaled by virtually anyone with the drive to do so -- no mountaineering skills or special preparations are needed, and most people entering this park are intent on conquering the summit (though only some 60% actually make it). Even if you're not interested in ascending Africa's highest mountain, the sight of Kili's snowcapped dome -- when she deigns to appear from behind the clouds that swaddle her for much of the day -- is a source of amazement; a result, perhaps, of the viewer being physically immersed in equatorial heat, while towering 5,895m (19,336 ft.) above the plains is the other-worldly glow of snow and ice.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.