One of the best reasons to visit the coast of mainland Tanzania is to recharge your batteries after an inland safari, where often you're up before dawn each day and careening around in a Land Rover for most of your waking hours. Many vacationers simply want to be left in peace after such an inherently "stressful" form of sightseeing, and the emptiness of the beaches north and south of Dar can be especially seductive if your fantasies are of seaside cocktail bars shaded by coco palms and lazy days with your toes in the sand. At worst, you might imagine yourself bobbing in the gentle surf or floating on the surface staring down at tropical fish through a pair of goggles. If you're less than thrilled by the idea of lying idle on impossibly white sandy beaches bronzing your body under a vast African sky, you'll be glad to know that there are usually plenty of waterborne activities such as snorkeling, boating, and fishing, offered at the various beach resorts. But for specialized pursuits such as diving and kitesurfing, you need to choose your destination carefully.

Kitesurfing -- Relatively new to Tanzania, kitesurfing relies on the Swahili Coast's seasonal winds: Between December and April, the Kaskazi brings speeds of between 15 and 30 knots, while the Kuzi blows from June to mid-September at about 15 to 35 knots. Either way, Dar es Salaam's South Beach area is ideal and easily accessible, and the relative lack of human clutter makes flying here a tidy prospect. Toby Mayers' TZ Kite Surfing (tel. 075/399-9001; www.tzkitesurfing.com) offers a variety of courses, from taster sessions to level 3 beginner courses, and also rents equipment.

Diving -- A wonderful place to dive -- sans crowds -- is at Ushongo Beach; besides the tranquillity of a little-discovered piece of paradise, Ushongo provides access to Maziwe Island Marine Reserve, which has been spared the destruction caused by dynamite fishing that's too common in Tanzania. Dives are operated by small, personal, and conservation-minded Kasa Divers (www.kasadivers.com) -- the only professional dive operation between Dar and Kenya -- which focuses on the spectacular coral garden in the reefs around the island. The diving here has been compared favorably with that in Zanzibar and Mafia, but the advantage here is the near-total absence of human activity, and the area is protected from fishing by a local community project. You're very likely to spot green turtles, and sightings of humpback whales and bottlenose dolphins actually increased in 2009. Owners Wim and Kerstin are experienced PADI instructors and offer a range of courses, from kids' level up to divemaster.

There's also fantastic, virtually undiscovered diving in the far southern town of Mikindani, near the Mozambican border. The marine park here, comprising Mnazi Bay and the Rumuva Estuary, protects a unique ecosystem, thanks to the movement of the Southern Equatorial current. Some of the most abundant and extraordinary marine life from across the Indian Ocean is found here, providing perhaps the best diving in East Africa -- more than 400 fish species and 258 types of coral have been recorded. Large pelagic fish, turtles, and giant groupers are common. Divers also regularly report seeing octopus, not to mention unusual specimens such as striped frogfish, ghost pipefish, crocodile fish, stonefish, and sea moth, and even varieties of seahorse that aren't easily identifiable. The excellent PADI center here was started in 2004 by Martin Guard, a marine biologist with years of dive experience who was drawn to the healthy and relatively undiscovered reefs. The focus is on low-impact dives, and his eco2 dive center (www.eco2tz.com) also functions as a marine research and education facility. The best place to stay in Mkindani is The Old Boma Hotel (tel. 075/636-0110; www.mkindani.com; £70-£110 double), a fine restoration of a century-old fort on a hill overlooking the ocean. The laid-back hospitality comes with a colonial, time-warp atmosphere, and there's a good pool in the garden where you can relax after exploring the marine park. Keen divers on a limited budget will find cheaper digs at Ten Degrees South Lodge (www.tendegreessouth.com), with just eight fan-cooled rooms, half of which have attached bathrooms. Mikindani -- accessed via daily scheduled flights to nearby Mtwara -- is a typical Swahili town, with idiosyncratic architecture, narrow streets overhung by first-floor balconies, and handsomely carved wooden doors. The town turns out to be a great place to imbibe some local culture between dives.

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.