Stretching for almost 650km (403 miles) between Dar es Salaam and the Rovuma River on the Mozambican border, the south coast of Tanzania has all the attributes one would expect of a tropical Indian Ocean idyll. There are endless white beaches lined with tall swaying palms, offshore reefs writhing with brightly colored fish, remote islands whose fisherfolk inhabitants cross to and from the mainland in dhows with billowing white sails, and any number of time-warped Swahili ports evoking the area's long history of maritime trade. Indeed, it could be argued that the most significant difference between the remote south coast of Tanzania and the better-known beach resorts of Zanzibar and Mombasa is simply a lack of publicity and the longstanding absence of anything resembling a conventional tourist infrastructure.
The south coast has long been a rewarding destination for travelers tolerant of challenging on-the-ground conditions. But this situation is slowly changing. The recent upgrade of the main road connecting Dar es Salaam to the Mozambican border (all but 48km/30 miles of which is now paved) has greatly improved access to the region, and there are also scheduled flights to Mtwara, the country's largest and most southerly port. Furthermore, the last few years have seen the opening of several new upper-midrange lodges aimed squarely at tourists, especially in the small towns of Kilwa Masoko and Mikindani.
For the architecturally and historically minded, the most worthwhile target along the south coast is Kilwa Kisiwani, which can easily be incorporated into a road safari to Selous. This small offshore island houses the most important ruins anywhere along the Swahili Coast of East Africa, the relic of a medieval gold-trading emporium described as "one of the most beautiful and well-constructed towns in the world" by the 14th-century globetrotter Ibn Buttata. The island lies directly opposite the well-facilitated mainland port of Kilwa Masoko, a crossing that takes about 10 minutes by motorboat, or anywhere from 15 to 60 minutes by dhow, depending on wind conditions.
From the mid-13th to early 16th century, Kilwa Kisiwani (literally "Kilwa on the Island") stood at the hub of a gold-trading network that linked the gold fields of the present-day Zimbabwean interior to Arabia and Asia. The decline of Kilwa was triggered by the Portuguese sacking of 1505 and sealed by the culinary attentions of the cannibalistic Zimba in 1587. Yet the haunted ruins that remain more than 4 centuries later form a peerless and compelling example of medieval Swahili architecture, one inscribed as Tanzania's second UNESCO World Heritage Site in 1981, yet still almost totally neglected by the tourist industry.
An imposing partially collapsed fort, known locally as the Gereza, dominates the shoreward side of Kilwa Kisiwani. This is a relatively modern building, built around 1800 during a brief Omani occupation of the island. A short footpath uphill leads from here to the main ruins, which include several mosques and palaces, as well as the ornately carved tombs of a succession of powerful sultans. The centerpiece of the old city, today as it was 7 centuries ago, is the Great Mosque, whose exquisite multidomed roof, supported by bays of precisely hewn arches, stands as the apex of medieval Swahili architectural aspirations. Ten minutes away, the cliff-top Husuni Kubwa (literally "Big House") was once the palace of the Sultan of Kilwa, and its sprawling floor plan includes a swimming pool and sunken audience court.
Back on the mainland, Kilwa Masoko (Kilwa of the Market), serviced by a quartet of fairly new tourist resorts, is the obvious base for exploring. From here, it is also possible to arrange diving and snorkeling excursions into the reefs of the Songo Songo Archipelago, where Songo Mnara Island has some well-preserved ruins contemporaneous with those on Kilwa Kisiwani. Also worth a visit, about 16km (10 miles) away by road, Kilwa Kivinje (Kilwa of the Casuarina Trees) is an atmospherically time-warped fishing village dotted with crumbling Omani and German mansions built during its 19th-century heyday as the terminus of the slave caravan route to Lake Niassa.
What limited tourist development exists south of Kilwa is centered on Mikindani, a sleepy Swahili port whose narrow alleys lined with two-story 19th-century homesteads evoke a far greater sense of place than the larger town of Mtwara, only 10km (6 1/4 miles) to its south. Literally "Place of Palm Trees," Mikindani was the starting point of the final ill-fated expedition into the African interior led by Dr. David Livingstone, who described it as "the finest port on the coast" but was rather less enamored of its "wretched" inhabitants. It is a beautifully sited port, home to a British nonprofit organization called Trade Aid, which funds community projects through sustainable ecotourism centered on the restored German Boma, and a diving center called eco2 that offers diving and snorkeling expeditions in the remote but ecologically pristine Mnazi Bay-Ruvuma Estuary Marine Park on the Mozambican border.