The 2 1/2-hour drive from Mto wa Mbu to Lake Natron, East African flamingo breeding site in the valley of Ol Doinyo L'Engai (the Maasai "Mountain of God"), is not for everyone. But if you like getting right off the beaten track and revere stark and desolate landscapes (and can take hostile heat, bumpy roads and relentless dust), this is arguably the most rewarding experience you will have in East Africa.
Technically, you can travel the 120km (74 miles) from Mto wa Mbu to Engaresero (also known as Ngare Sero, the nearest village to Lake Natron) overnight, then set off across more bone-jarring tracks to Klein's Gate in the northern Serengeti, but the latter half of this drive -- which can take 5 to 7 hours, depending on road conditions -- is demanding on backs, vehicles, and tempers; most operators will try to persuade you to back-track from Lake Natron, heading back (on the same road) to Mto wa Mbu. If you are an intrepid traveler and inveterate camper, it's worth finding a reputable operator who will traverse the Ngorongoro Conservation Area from Mto wa Mbu to Klein's Gate, as I have met a number of people who have done the journey -- some more than once -- and all rate it as "awesome" (one of the best people to arrange this through is Horst, proprietor of Meru View; firstname.lastname@example.org or www.matembezi.co.tz). However, returning the way you came the following day (or later, if you want to climb Ol Doinyo L'Engai) is no hardship, given the jaw-dropping landscapes, now seen from the reverse angle and probably in a different light.
Aside from the sheer scale and brutality of the landscape, there is the luxury of savoring it all on your own; there are no road-side stalls or signs of tourist activity en route, and you are unlikely to pass more than a handful of other vehicles during the entire round-trip. What you will encounter are some of your most treasured memories of the Maasai. Traversing seemingly barren valleys, Maasai men stride like kings before their cattle, their tall, lean frames draped in artful shades of red, a startling contrast against the parched backdrop; similarly, the women are usually wrapped in blue, their white-beaded manacles gleaming against their elongated necks and slim wrists.
With the exception of Engaresero village, the Maasai here live pretty much untrammeled by the cultural tourism that has turned villagers living within easy reach of the Ngorongoro Crater into attractions. Trigger-happy photographers are urged to practice the utmost restraint. (Note that some Maasai living here prefer not to have their photographs taken; others, like elsewhere, will expect to be paid. Always ask first, and respect the response.)
Most visitors travel this way ostensibly to get a close-up look at Lake Natron, breeding ground for the Rift Valley's 2.5 million endangered lesser flamingo. Along the way, you will also pass by the 500-year-old Engaruka Ruins. Once a thriving terraced city with a sophisticated irrigation system, it is today of limited interest to visitors without a strong archaeological bent. Of far more importance is the approaching bulk towering 2,878m (9,440 ft.) above the blackened plains -- Ol Doinyo L'Engai, the last remaining active volcano in the Great Rift Valley.
Active for more than a century (the first recorded observation dates back to 1883; the last smoke seen spewing from the mountain was in June 2008), the rumblings emitted by the mountain are believed by the Maasai to be the voice of their female deity (eruptions seen as her fury). Aside from its spiritual significance, the beautiful symmetry of the mountain is one of the most arresting sights in East Africa. Entirely barren, its single-cone peak dusted in white ash, the triangulated shape rises from flat plains that are blackened and strewn with volcanic rock. Hot and hostile, it is as humbling as any of Earth's great natural wonders, a truly surreal and post-apocalyptic vision that will have you stopping your vehicle every few minutes to try, yet again, to capture it all on film.
By contrast, Lake Natron, its shallow, caustic waters surrounded by sludge-gray volcanic ash and pink and white crusty salts, is, unless seen from the air, not a photogenic destination, but a fascinating natural phenomenon nevertheless.
Like all Rift Valley lakes, Natron has no outlet, and during the driest months, when evaporation is at its highest, the pH concentration can shoot as high as 11, turning its waters as alkaline as ammonia. Even mud temperatures can reach 60°C (140°F), an inhospitable environment for most living organisms, but an ideal nursery for salt-loving microorganisms, including cyanobacteria, whose red pigment produces the deep-red colors seen in the central parts of the lake, changing to orange in shallower water. The saline waters are also much loved by the blue-green algae with red pigments that forms the primary diet of the lesser flamingo and gives its feathers its glamorous pink hues.
Flamingo breeding season is usually around June, when they congregate in the center of the shallow waters, the caustic and hot muddy surrounds safeguarding them from predators, before moving to the southern shorelines and finally migrating to other soda lakes in the Rift Valley. You can arrange excursions to the breeding grounds (a drive of 25km/16 miles from the village) or, depending on time of year, to the southern shoreline, from Lake Natron Camp . If the flamingoes are resident on the southern shoreline, a wonderful excursion is to walk, accompanied by a guide, to the lake in the late afternoon, when the softer light and lower temperatures transform what is otherwise a physically inhospitable environment. The walk takes approximately 90 minutes; set aside some more time to photograph the waterfowl (aside from flamingoes, you will see plenty of egrets, herons, and pelicans), then settle down at the table that has been set up for you by camp staff and enjoy a chilled bottle of wine before being transferred by vehicle (or you may opt to walk) back to camp.
Lake Natron Camp will also make all the arrangements, should you wish to climb Ol Doinyo L'Engai. Ascending more than 2,000m (6,560 ft.) in 5 hours, this is a tough, steep climb, rated by some as the best 1-day trek in Africa and more exhilarating than conquering Kilimanjaro. Due to the heat the lunar-like landscape radiates, climbers set off at midnight, reaching the summit at dawn, making the 2-hour descent before the sun climbs too high.