The cloud-topped summit of Ol Doinyo Lengai, an active volcano that last exploded in 2008, looms over the crater highlands, with the outlines of hardened lava flows striping the slopes.
Like rumbling thunderclouds or far-off explosions, the muffled booms broke the silence as we reclined on a slope of pulverized lava beds in a small passage near the top of a volcano in East Africa, nearly two miles up into the night sky.
It was 5 a.m., and for six hours we had been scaling the colossal, pyramid-shaped Ol Doinyo Lengai — through waist-high tufts of grass in powdery ash and loose rock and tight crevices.
Ol Doinyo L’engai is a Maasai term meaning “The Mountain of God,” because the natives believe that the roaring of its volcanic actions was ‘God Speaking!’ the mountain is also their shrine.Geoparks Africa
The journey took us through over hardened lava flows so steep I had to climb on all fours.
Now we were exhausted, resting inside a fissure with chalky white walls.
At sunrise, we would clamber the remaining 15 minutes onto the rim of the crater.
Our bed of gravelly black lapilli was warm, as if heated by an electric blanket. At my knee, a vent in the rock emitted swirls of steamy gas.
“You hear that noise?” my friend Kaixu Yuan asked.
“Yeah, it’s a thunderstorm in the distance,” I reckoned.
“That’s the volcano underground,” Dennis Laiza, our Maasai guide, said.
I was starting to understand what it actually meant to be atop an active volcano.
We were nearing the spectacular climax of our grueling and astonishing weeklong journey through the Crater Highlands of Tanzania.
The region sprawls along the East African Rift, where, millions of years ago, separating tectonic plates allowed magma to rise, belching out over many millenniums a multitude of volcanoes, many of them now collapsed calderas or dormant peaks.
The most famous of the mountains is Kilimanjaro, the highest point in Africa (19,340 feet), 100 miles to the east. Kaixu had booked a flight from New York with no set plan and wanted company. I’m not a big fan of snow or thin air, so I searched for an alternative adventure.
I was intrigued by the highlands and selected a mix of experiences: a safari in the Ngorongoro Crater, the world’s largest volcanic caldera, 14 miles wide and said to contain an astounding abundance of wildlife; the Empakaai Crater, nearly four miles across and one of the few in the region filled with a lake; and Ol Doinyo Lengai, the only volcano in the world to emit natro-carbonatite lava — dark gray, relatively cool (about 950 degrees Fahrenheit) and fast-flowing.
I used instagram to send out requests for guides and chose a relatively new tour operator named Daudi Minde.
We settled on a trip that would include two nights camping, a 10-hour trek and four nights in a hotel and lodge, for $1,750 per person.
The tour was poles apart from luxury safaris with furnished tents and balloon rides over the Serengeti. Daudi cobbled together freelance guides, a borrowed, old Land Cruiser and no-frills accommodations for a trip that took us to places we surely would have missed without the aid of local specialists.
After landing in Kilimanjaro airport (I flew from Thailand, where I live), we spent the night in nearby Arusha at the Green Mountain Hotel, which, like most in the cities, was behind tall walls and a metal gate.
At 6:30 a.m., our guide, Aidano Kayala, and cook, Ramadhan Singano, had the Land Cruiser crammed with camping gear. We drove west past the ramshackle shop fronts, women grilling corn on the dirt roadside and ranks of young men on chrome-fronted motorcycles waiting for fares.
We knew we were in the wild when, two hours outside the city, a bull elephant lumbered across the road, spun around and blared his raised trunk, then rammed an acacia tree, showing off his strength or scratching his head.
At the entrance to the Ngorongoro Conservation Area, where, unlike in Tanzanian national parks, the Maasai are permitted to establish settlements and graze livestock, the steep dirt road was being rebuilt with crushed rocks.
Two Land Cruisers were tipped and stuck at 45-degree angles, and Aidano roared past.
We stopped at the overlook to behold the vast circular chasm. In November, at the tail end of a five-month dry season, the landscape was parched. Cloud shadows darkened sections of the leafless rim and the tan crater floor.
A silvery green lake spread out on the left, and a patch of emerald woodlands near a stream stretched out on the right. Wildebeest appeared as black dots in the buff.
The 45-minute bucking bronco of a ride down the rim ended at a marsh, where we ate a tasty boxed lunch of mustard-ginger chicken stew.
We gazed at a submerged hippo, a few curly-horned buffalo and a wandering warthog.
As we jolted along a corrugated path past a line of pale pink flamingos in the shallow lake, a troop of baboons along the roadside and a herd of diminutive Thompson gazelle in the scrub, two things became apparent: The crater was mostly empty, and the wildlife was doing a lot of loitering.
In the rainy seasons, the expansive floor is lush and teeming with animals, including massive herds of migrating wildebeests.
And because nearly all of the inhabitants are herbivores, we saw no chasing and fleeing.
Instead, the wildebeests milled about or rested in acacia shade, and the zebras did a lot of standing around, motionless, like they were trying to remember something they’d just forgotten.
Still, the variety of free-roaming animals, unfazed by the few dozen Land Cruisers clattering across the crater, was captivating.
“This definitely is an animal paradise,” Kaixu exclaimed, observing through the pop-top. “Except for the lions.”
“Don’t you worry about that,” Aidano said. “I am the expert. I know where to look.”
After a futile search for the endangered black rhino — or any rhino — in the forested floodplain, we drummed toward our exit at the back of the crater, passing hundreds of wildebeests, buffalo and zebras and stopping to watch a bull elephant with long white tusks sauntering through the congregation.
A pair of ostriches stood by the road. Crown cranes strutted and spread vulture-like wings.
“Is he dead?” I heard Kaixu exclaim.
We’d finally found a lion.
But he was napping, his back to us about 20 yards away, his dark mane quivering in the wind.
We rumbled up out of the amphitheater just before sunset and pulled into a glade near a Maasai village.
One of its warriors, Maleton Oleriro, tall and draped in a red blanket, would be our guide for the next two days. We talked as the fire of damp wood hissed and smoked.
Maleton told us how his late father had six wives, how his own arranged marriage three years ago included a dowry of 20 cows, and how he trained to be a Maasai warrior with other boys by practicing spear-throwing while herding cows.
The next morning, we rattled over to the rim of Empakaai Crater, an enchanting circular caldera about four miles wide and 1,000 feet deep, largely covered by a lake.
The wind, sun and clouds created an impressionistic canvas on the gleaming surface.
We traipsed down a steep, dusty path, through a thick forest and onto a shoreline of stubby grass and sand. We were alone but for several thousand flamingos rimming the edge of a quarter of the deep lake in a pink arc.
I tasted the water (not too brackish) and asked Maleton if swimming was allowed. He didn’t know: “Maasai don’t swim,” he said.
That ambiguity, and the fact that a stream fed into the lake, settled it.
I stripped down in a warm breeze, squished into the muddy shallow and dove into the cool, rust-colored water. I closed my eyes and swam freestyle, feeling the soft, buoyant water and how the salinity stung my tongue.
Heading toward a flamboyance of flamingos on the right side of the shore, breast-stroking as stealthily as possible, I approached several large birds that paddled out close to me, but they suddenly lifted off.
I put my head down and pulled toward the shore, and, when I looked up, several hundred were streaking across the sky.
I swam backstroke, noticing how dark their wings were underneath and how their pink stick legs acted like tails.
We hiked for four hours toward another Maasai village, joined by five women selling bracelets and carrying firewood.
They sang a song of praise and fertility as we walked amid a primeval panorama of mountain ranges and a dazzling rainbow arcing toward our ultimate point, the Ol Doinyo Lengai volcano.
The next day, our tents and gear saddled on two small donkeys, we embarked on an all-day hike — across a misty valley, through an ashy acacia forest and onto an escarpment that ran for miles down through the mountainscape.
As a massive curtain of clouds lifted, we could see part of the Serengeti plains far beyond on the left, the sled-shaped Lake Natron way off in front and the remote volcano to our right, its top crowned with a cloud mass bigger than the mountain.
We stopped in a dry riverbed with stratified walls and shared our beef stew with five passing Maasai boys.
They all wanted to be warriors like Maleton, and we took turns launching a walking pole down the ravine in a spear-throwing contest.
Kaixu and I came in last. In the afternoon, we reached the bottom and waited on a hillock for Aidano to drive us to Lengai Safari Lodge.
A sandstorm was building, horizontal whirlwinds racing down the canyon and obscuring the lake in the distance.
A Land Cruiser finally arrived, but it was driven by Dennis Laiza, the Maasai guide who would take us up the volcano.
Aidano had gotten stuck in deep ash a few miles away. We rumbled over and spent 20 minutes pushing and towing Aidano’s truck out of the depression.
That night we dined on a local dish called ugali, a polenta-like mash that you ball to sop up stew with your fingers, and washed it down with Kilimanjaro lager.
After spending the next morning swimming at a crystalline waterfall near the lodge, we rested and at 10:30 p.m. headed out to Ol Doinyo Lengai.
Volcanologists estimate that the volcano started forming some 370,000 years ago. Explosive eruptions come every generation or so, with the last one occurring in 2007 and 2008.
After another jolting ride along an undulating, sandy path, we set out up the west slope at 11:15 p.m., trudging through the tussocks and powdery dark ash.
Around midnight, we came across tracks. “Lion,” Dennis said, assuring us that they keep away from the lights. I kept close to the pack, determined to not end up as prey.
The wind was picking up, but the temperature was still in the high 50s.
The nearly full moon was dim behind a shroud of gauzy clouds. A drizzle speckled the parched stone with little black spots.
The route became steeper. The ground was a mix of loose stones and sand so deep we slipped back several inches with every step up.
We scrambled up to the rim just before the sun broke the horizon next to Kilimanjaro.
In a whipping wind, we looked down about 20 stories into an entrancingly beautiful cauldron of rising steam and sputtering lava.
The crater was about 200 yards across, stratified brownish cliffs encircling a moonscape of rough formations and sculpted hornitos in multiple shades of gray and white.
Columns of gas rose from vents around the circle. In the middle, surrounded by arabesque flats that looked like crusted lakes, loomed a profusion of large cones, with jagged holes at the tops.
The largest one was smooth and gray, and when the wind died down we could hear lava churning and spitting like some seething creature from the netherworld.
Every minute or so, burst of black beads splashed out of the hornito, tumbling down the sides.
I jogged briefly around the rim, stopping to contemplate the molten energy that shaped these highlands, and hoping for a nonfatal, but sizable, eruption.
But after about an hour, it was time for the teetering six-hour descent. The rising sun, heating the entombed lava slopes, was casting a pyramid shadow over the landscape far below.