Uganda can still be regarded as one of the off-the-beaten-track destinations in Africa. Although it is popular for Gorilla trekking, there is only space for 32 gorilla treks per day. This can hardly be called crowded. Other destinations in Uganda are little known compared to Kenya and Tanzania which are established safari destinations. Having said this, it does not mean they are inferior, just less well-known.
Other than gorilla trekking, Uganda is home to chimpanzee and golden monkey trekking. Gorilla trekking in easily combined with a safari, including tree-climbing lions, in the Queen Elizabeth National Park. Kibale National Park is one of the best places to interact with habituated chimpanzees. Murchison Falls National Park offer the beautiful falls, boat trips and fantastic birding. Semuliki National Park and Semliki Safari Area are more remote and offer great birding and time to relax in a scenic setting.
Kidepo Valley National Park is on the border of South Sudan and is much drier than the rest of Uganda. These conditions make for a great safari and also offer a different variety of birds. Jinja is the source of the longest river in Africa, the Nile. It is also the adventure centre of Uganda. Try you hand at white water rafting, bungee jumping over the source of the Nile, kayaking and quite a few other adventure activities.
I have mentioned birding several times. Uganda must rate as one, if not the, premier birding destinations of the world. With over 1000 species, including many endemics, twitchers salivate at what is on offer.
For such a small country, Uganda offers a surprising diversity of experiences. Combine this with the friendly, hospitable people and it becomes a truly spectacular experience. One for the bucket list.