It's hard to imagine what the world might look like following the collapse of humanity.

For astronaut George Taylor, Charlton Heston's character in 1968 film Planet of the Apes, it looked very much like this.

Surging skyward from millennia-old riverbeds parched crisp by the sun, hundreds of steaming fumaroles and limestone chimneys served as a fitting backdrop for the post-apocalyptic sci-fi movie.

As I weave through spiralling calcareous sculptures silhouetted by a jaundiced bitter yellow sunset, a mosaic of salt flats pops and crunches underfoot. On the horizon, a woman cloaked in billowing purple silks navigates a herd of goats and donkeys through a dusty haze.

There's no sign of Taylor's forlorn Statue of Liberty submerged in the sand, but I share the same sense of discovering a forgotten civilization from a lost period in time.

Dali-esque landscapes

I'm standing on the flamingo-streaked shores of Lake Abbe in Djibouti, a small country in the Horn of Africa, bordering Ethiopia, Somaliland and Eritrea.

A charred, volcanic wasteland, it sits in the centre of the Afar Triangle, where three pieces of the Earth's crust are slowly shifting apart, and forms part of the Great Rift Valley, a continuous 6,400km geographic trench that's visible from space.

[Related story: How much would it cost to visit all 7 Wonders of the World?]

Aside from a brief flirtation with Hollywood, the only international interest in Djibouti has been a military one. The former French colony provides a safe and stable base from which to monitor a volatile region, where civil war is raging 20 miles across the Bab-el-Mandeb Strait in Yemen, and the threat of Somali pirates still hangs over the Gulf of Aden and the Red Sea.

Proximity to war zones, poor infrastructure (there are few roads and no hot water in the entire country) and a population that swings between inquisitive and inhospitable, hardly provide the platform for a thriving tourist industry.

Yet the opportunity to explore Dali-esque landscapes plucked straight from the pages of National Geographic is too good for adventurous travellers to turn down. I've joined Explore Worldwide's first escorted tour through the region and it's completely sold out.

Travelling in a convoy of 4WDs, we thump and bump over rocky, arid terrain, through deserts dotted with thorny acacia bushes and little else. It's a hostile environment, and inhabitants are suitably abrasive.

As we approach a nomadic settlement of huts built from sun-bleached branches, our drivers speed up. Unruly children from the Afar tribe chase the vehicles, some throwing stones, others cheekily poking out brilliant pink tongues from jet black faces, while their shy Muslim mothers hide beneath a swirling mass of colourful fabrics.

Even as I raise my camera, our driver, Ermi, shakes his head.

"They won't like it," he says, as another rock bounces off the bonnet.

It's easy to understand why local people are so suspicious; up until now, few tourists have bothered to come this far. It's more common for foreigners to congregate in coastal areas, attracted by pristine coral reefs and the opportunity to swim with juvenile whale sharks.

Gentle sea giants

Jason Shrewsbury from local operator Dolphin Services offers to take me out on a skiff boat in search of the gentle sea giants. Originally employed at the American military base, the blond, 20-something dive instructor developed a passion for the marine world while stationed here.

"These days, everyone stays in their bases," he laments as we leave the busy port of capital Djibouti City, which is choked with liners transporting goods to neighbouring Ethiopia. "But the best part of Djibouti really is underwater."

From November to January, whale sharks feed in these clear, warm waters and tourists have the chance to snorkel alongside them. As soon as we catch sight of a polka-dotted creature, I dive in and, like a bunny in a juggernaut's headlights, find myself staring into a gaping, metre-wide, pillar-box mouth.

More interested in measly krill than a meaty human, the largest fish in the sea glides past and disappears into the inky depths as I frantically struggle - and never succeed - to catch up.

After an hour spent swimming along the coast, where butterfly fish and manta rays lurk beneath table coral big enough to host a deep sea banquet, I agree with Jason about Djibouti's marine merits.

It would, though, be unfair to dismiss the rest of the country.

Sobering sights

The rubbish-strewn Yemeni refugee camps surrounding Djibouti City don't make for comfortable sightseeing material, yet they give a sobering insight into a detached, troubled world often only viewed through TV screens. (Last year, David Beckham came here as part of his project 7: The David Beckham Unicef Fund.)

At times life feels almost as worthless as the plastic bags rolling like tumbleweed in the dust, and there's an unavoidable sadness about Djibouti, a sense it's been abandoned.

But beyond the rusting water canisters left here by aid workers and bottle tops moulded into the mud, is a geological wonder world comparable to nowhere else on earth. From the petrified Day Forest National Park in the Goda Mountains, to the lowest point in Africa, the vividly turquoise and heavily saline Lake Assal, there's a wealth of natural attractions.

With a bit of love, it could have so much potential.

[Related story: Holidaying alone: 9 singular places every solo traveller should visit]

The Ethiopian government and their Chinese investors clearly think so, and have spent several billion dollars on a train line to link Addis Ababa with the port in Djibouti City, one of Africa's most important trade routes.

Our journey to Djibouti also started in the Ethiopian capital, and Explore's decision to combine the two countries in an itinerary is wise. With tribal groups spilling across the border, there are clear cultural similarities and a trade dependency means fortunes are inextricably linked.

Developing in harmony

In contrast to its stagnant neighbour, Ethiopia is developing at an accelerating pace. In the last few years, several thousand kilometres of road have been asphalted, and while driving across the country, we share carriageways with wooden carts piled high with hay bales and women in burkas riding horse back.

The famine-ridden Band Aid years have been consigned to the past and a new picture of progress is emerging.

Bucking perceived stereotypes, Ethiopia can be remarkably green (and cold) as I discover on a trek through the Bale Mountains in search of endangered nyala, giant mole rats and Ethiopian wolves. Condensation rises from ponds and thick clouds suffocate the basalt landscape as we race to beat falling darkness and plummeting mercury levels.

But perhaps most remarkable of all is the degree of religious harmony, with Muslims and Christians co-existing peacefully. The medieval walled city of Harar even earned UNESCO status for being "a city of tolerance, peace and diversity".

A high percentage of the population is addicted to chewing khat, and as I sidestep over men sprawled supine in the street, one with a bunch of hibiscus flowers wedged into his hair with an afro comb, I wonder how much the natural stimulant is responsible for the laidback, carefree vibe.

Regardless of religion or ethnic grouping, the people here share a sense of national pride. That's one "good" they might want to consider exporting to Djibouti.

Sarah Marshall was a guest of Explore (01252 884 723) who offers a 12-day Addis to Djibouti Adventure trip from £2,359pp. The price includes return flights, 10 nights' hotel and one night camping accommodation on a bed and breakfast basis, most meals, transport and the services of an Explore Leader.