Having visited many national parks, Nyerere National Park is certainly one that I have a real soft spot for. Not only is it the largest game reserve in Africa, as well as boasting one of the largest remaining populations of African Wild Dogs, it is also a UNESCO World Heritage Site due to its diversity of wildlife.
Selous is also a top spot for walking safaris and boat cruises on the mighty Rufiji River, the latter well worth incorporating with sundowners. But for me, what's also important — in addition to excellent game viewing — is the lack of crowds, which makes Selous a must-see for safari purists.
Finally, if that wasn't enough, Selous is historically interesting for many reasons, but perhaps the more notable one being the place of its namesakes demise, the great Frederick Courteney Selous.