(CNN) — "Going up that river was like traveling back to the earliest beginnings of the world ... an empty stream, a great silence, an impenetrable forest," wrote Joseph Conrad in classic novella "Heart of Darkness."
He was speaking of a journey along the Congo River, but the same could be said for any great African lake or river.
Even more than the deserts, mountains and great plains, the continent's waterways reflect the blend of wildness, beauty and serenity that initially draws people to Africa and keeps them coming back.
"Water journeys in Africa are particularly alluring because rivers are communication channels and lifelines," says Guy Lankester of From Here 2 Tumbuktu, an adventure travel company that books trips on the Senegal and Niger rivers in West Africa.
Here are 10 of Africa's most impressive water adventures:
1. Houseboating the Chobe River (Namibia and Botswana)
Zambezi Queen offers safari cruises along the Chobe River, which is known for its impressive wildlife.
Zambezi Queen Collection
The floodplains of the Chobe River nurture the world's largest concentration of elephants -- an estimated 120,000 animals munching their way through the lush grass and floating vegetation.
Given the moist terrain, the best way to rub shoulders with all those pachyderms is a river trip on boats like the Zambezi Queen -- a 42-meter luxury safari houseboat.
Starting from Kasane, the vessel heads upriver into the heart of Chobe National Park on two- and three-night voyages. Tender boats are used to get even closer to the waterfront wildlife.
"Elephant sightings along the river are very special indeed," says Wayne Suttie of the Zambezi Queen Collection. "The matriarchs bring their family groups down to the river to bathe and drink ... with the herd taking care of the babies right in front of the tender boats."
2. Rafting the Batoka Gorge (Zambia and Zimbabwe)
Zambezi rafting through the Batoka Gorge, which is in between Zambia and Zimbabwe.
Courtesy Rafting Zambezi
After tumbling over Victoria Falls, the Zambezi River makes a mad dash through the Batoka Gorge, a colossal slash in the Earth's crust that separates Zambia and Zimbabwe.
With more than 30 rapids ranging up to Class V -- with names such as Oblivion, Deep Throat, Terminator and Ghost Rider -- the stretch of river through the Batoka Gorge makes for one of the world's wildest rafting rides.
"It's the best river on Earth," says Hamish McMaster, owner and founder of Zambezi Rafting. "Warm water, stunning beaches to camp on. The perfect blend of excitement and relaxation." Zambezi Rafting offers a range of float trips, from half and one day journeys through Batoka Gorge to seven-day expeditions that travel the river all the way down to Moemba Falls.
3. Kayaking the Nile (Uganda)
Whitewater rafting is an exhilarating way to explore the world's longest river.
Courtesy Kayak the Nile
Victorian explorer John Hanning Speke spent years searching for the exact source of the River Nile.
Nowadays that location -- where Lake Victoria overflows to create the Nile in central Uganda -- is a hub for adventure kayaking on the world's longest river.
The whitewater starts beside lakeshore Jinja, an alternating series of rapids and flat water as the Nile darts north at the start of its long journey to the Mediterranean.
Full and half-day guided paddle trips are the norm, but Kayak the Nile also offers a four-day "Navigate the Nile" kayak camping adventure that cruises a 50-kilometer stretch of the river down to Hairy Lemon Island.
4. Congo River expedition (Democratic Republic of the Congo)
The Congo River Expedition is an extensive 1750 kilometer journey between Kinshasa and Kisangani.
Photo by Chris Rosenkrans, Congo Travel and Tours
Made famous by "Heart of Darkness," the Congo River retains much of its edgy vibe as it flows 4,700 kilometer from the Katanga Plateau to the Atlantic Ocean.
The classic trip is a multiweek journey on local ferries or barge boats between Kisangani and Kinshasa, waterfront cities on either side of the Democratic Republic of the Congo (DRC).
"The appeal of the greatest river journey -- and perhaps greatest journey of Africa -- is that it leads through what is still the real 'last terrestrial frontier' outside the Antarctic," says Chris Rosenkrans of Congo Travel and Tours.
However, he cautions that the Congo trip isn't for everyone, and participants should "come with plenty of patience, realism, hardiness and humor."
5. Steaming across Lake Malawi (Malawi)
MV Ilala travels across Lake Malawi to Chilumba.
Courtesy Malawi Tourism
A relic of the British Empire, the steamer MV Ilala has been carrying passengers and cargo across Lake Malawi since 1951. Now in its fifth reincarnation, the latest version of the ship undertakes a six-day round trip between Monkey Bay and Chilumba once each week.
Among the nine stops along the way is historic Likoma Island, where David Livingstone established his missionary headquarters in 1880.
Four different classes of accommodation are available on the 400-passenger ship, from lower deck steerage to the comfy Owner's Cabin.
6. Senegal River cruise (Senegal)
Bou El Mogdad cruises from Saint-Louis Senegal to Podor.
Courtesy Bou El Mogdad
Draining the western edge of the Sahel and Sahara, the Senegal River forms a watery boundary between Senegal and Mauritania.
An old French colonial steamer called the Bou El Mogdad makes the journey from Saint-Louis on the Atlantic coast.
The seven-day round trip includes stops at Djoudj Bird National Park, La Folie du Baron Roger, Dagana and Podor.
Built in Holland in 1950, the Bou El Mogdad features 23 modernized cabins and two luxury suites, as well as a restaurant, bars, swimming pool, massage room and library.
7. The Okavango by mokoro (Botswana)
Mokoro canoes are used to travel through the wetlands of Okavango Delta.
Courtesy African Bush Camps
Once part of an inland sea, the vast Okavango Delta is one of the world's largest wetlands, a refuge from thousands of different animal species as well as the indigenous people who inhabit this watery wilderness.
For hundreds of years, mokoro dugout canoes have been the main mode of local transport through the wetlands. The boats are propelled through the shallow water with a long pole -- in a similar manner to English punting.
Many of the safari camps and lodges around the edge of the Okavango offer game-viewing in mokoros, including Khwai Tented Camp and Linyanti Bush Camp on the Delta's northeastern side.
Like other muscle-powered watercraft, mokoros can approach waterfront game in absolute silence, which is often the only way to get close to shy swamp-dwelling creatures such as the lechwe and sitatunga (types of antelope).
8. Canoeing the Lower Zambezi (Zambia)
The lower part of the Zambezi River is full of remarkable wildlife such as elephants, crocodiles and hippos.
Downstream from Lake Kariba, the Zambezi River flows wild and free again on its way to Mozambique and the Indian Ocean.
The best way to thread the river's maze of sandbars, shallows and grassy islands is via canoe, and guided paddles are offered by waterfront digs such as Chongwe River Camp in Lower Zambezi National Park.
The wildlife show along the Lower Zambezi is often spectacular -- elephants swimming across the mile of water that separates Zambia and Zimbabwe and hippos baring their teeth to warn you away.
Although veteran canoe guide Matt Porter cautions that you should give hippos plenty of clearance, he's also got a soft spot for the lumbering creatures.
"Hippos are much maligned," he says. "You often hear that they kill more people than any other African animal, but the fact is they shun human contact, especially in the water."
9. Cruising the Nile (Egypt)
Luxury cruise ship Oberoi Zahra sails across the Nile between Luxor and Aswan.
Why walk like an Egyptian when you can sail the River Nile? Whether it be on a luxury cruise ship such as Oberoi Zahra or sleeping under the stars on the deck of little felucca, a journey down the Nile is on the wish list of nearly every bona fide globetrotter.
The most popular route is between Aswan and Luxor, a journey that normally takes around three days -- with stops along the way at ancient Egyptian temples in Kom Ombo, Edfu and Esna.
Longer journeys ply the entire river between Aswan and Cairo. Another alternative is cruising across Lake Nasser on a retro steamer called the MS Eugenie, a voyage that ends at Abu Simbel.
Those who want to explore the river by sailboat should bargain with the felucca captains along the Aswan waterfront for the best rate.
10. Maroantsetra wetlands by motorboat (Madagascar)
Exploring the waterfront wildlife of Madagascar's Maroantsetra wetlands by motorboat.
Far off the beaten path even for Africa, the Maroantsetra wetlands sprawl across the mouth of the Antainambalana River as it flows into big Antongil Bay on the island's eastern shore.
Casting off from the market town of Maroantsetra, a motorboat tour of the wetlands and river is a cool way to observe waterfront wildlife and the means by which local people have meshed the maze of waterways into their daily lives.
Chameleons of various shapes, sizes and colors are out and about during the daytime, clinging to waterfront vegetation as they wait for the next meal to buzz within tongue-striking distance.
After dark there's a whole different cast of wetlands creatures. A tiny mammal called the streaked tenrec. And the big eared, bug eyed aye-aye -- a lemur that's also the planet's largest nocturnal primate.