Geothermal wonders Iceland

Every so often, the colossal power buried under Iceland’s dramatic surface makes itself known to the world. In 2010, the eruption of Eyjafjallajökull volcano in the island’s south downed planes for days and, more recently, the fiery splutter and gush of Fagradalsfjall, Litli-Hrútur and Sundhnúkur have set the news aglow. Iceland sits on both the Mid-Atlantic Ridge and the Iceland hotspot, resulting in an extraordinary number of earthquakes and eruptions, as well as more friendly geysers and hot springs. Around 30 active volcanic systems have helped create an ever-changing playground of mountains and balleys, lava deserts and fields. Glaciers cover around 11 per cent of the country, with the vast Vatnjökull spilling across the south-east; and glaciers, snow and rain are responsible for the thundering waterfalls from north to south. The mix of cold and heat has produced unique glacier caves, and touring these cathedrals of ice is an unearthly experience as you enter a translucent blue vault surrounded by smooth, sinuous walls and frozen, hushed breath.

Naturally, the hot springs are a must. In March, seismic activity briefly closed the iconic Blue Lagoon, leaving tourists bereft. The lagoon is actually man-made, its milky waters provided by a nearly geothermal power station. For a more natural dip, head to smaller, local, outdoor springs or the remarkable Reykjadalur hot river, which streams its way through a lime and chocolate valley.

Wildlife encounters Indonesia

The crack of a twig high above is the first sign something is up there. A section of rustling leaves tries to cling to its tree to no avail: the branch breaks off to reveal the gingery fur, pot belly and bulbous nose of a hungry proboscis monkey, just one of Borneo's extraordinary collection of animals and plants. The island's 130 million-year-old rainforest is a biodiversity hotspot that has long lured noted naturalists like Alfred Russel Wallace to its shores. It has swamps, mangroves, myriad forest types and the earth's tallest tropical trees, which soar above intrepid trekkers. Hiking here isn't always a breeze and the cool drip of dew from overhanging leaves is a welcome relief when wading through the jungle's humidity. So too is the network of rivers that break up its stretch, where you can make quick headway with canoes or motorised kayaks. Tours to Borneo also cover culture, with visits to longhouses to eat with local tribespeople. Wildlife enthusiasts can look out for endemic species like the Borneo elephant, Borneo clouded leopard, and the beloved orangutan. Meanwhile, floral aficionados - spoilt with some 1,700 orchids and plentiful carnivorous pitcher plants - may face a more olfactory adventure. Borneo is home to the world's largest flower, the rare rafflesia, nicknamed 'the corpse flower' for good, overwhelmingly pungent reasons.

Ancient world Vietnam

History permeates Hue like incense on the warm breeze. The former capital was the home of the Nguyen Dynasty, the last ruling family of Vietnam, who left a trail of royal tombs and a great in ornate beauty, drawing eyes to its tiled and carved architecture. Hue’s ancient tombs are steeped in atmosphere. At Tu Duc’s blotched across the stone speak to its age, while statues of silent soldiers stand guard at the entrance of Khai Dinh’s mausoleum.

Down the coast is the colonial city of Hoi An. Once a thriving port, trade bought Japanese and Chinese influence, seen in sites like the handsome Japanese Covered Bridge, elaborate Hoi Quan Phuoc Kien Assembly Hall and the artifacts inside the saffron Tan Ky House. Just outside Hoi An lie the centuries-old Champa ruins of My Son Sanctuary, encircled by mist-strewn mountains and veined with the sacred waters of the Thu Bon river, its crumbling steps and phenomenal brickwork slowly being splattered with vibrant green as nature finds a home in their nooks.

Vietnam’s ancient centre is an amazing place to cycle, trundling through untouched countryside and old settlements, battling uphill for the soaring views at Hai Van Pass.

Mountain high Nepal

Mount Manaslu spikes up from the Himalayan heights like a dog tooth; the eighth highest peak in the world, at 8,163m, it towers just north-west of Kathmandu. Nepal’s corrugated border follows along the world’s highest range, making it the ultimate place for awe-inspiring, breathtaking mountain scenery. For a long time, Manaslu, whose pale, split peak is best seen at dawn, has lived in the shadows of Everest and K2, but the mountain isn’t just overlooked by mountaineers: while the Annapurna Trek is considered the ultimate Nepal journey, lurking on bucket lists around the world, Manaslu’s circuit is a quieter, no less extraordinary adventure. There are plentiful day walks from the Himalayas, slowing down the stomach-stirring altitude as you head skyward and letting you feel every inch of the elevation as fresh air chills your lungs. Manaslu’s circuit traverses the conservation area close to the Tibetan border, taking in the Larkya-La Pass and Mt Manaslu’s base camp. The way is peppered with forests, terraces, valleys and villages like Tilje, Samdo and Samagon, where hospitable locals await with steaming tea.

Amazon exploration Brazil

When it comes to spotting jaguars, everything stands still. Body taut and breath held, eyes dart, binoculars at the ready, searching for a velvet foot or spotted tail or the glint of an amber eye looking back. Only the soft lick of water at the boat’s hull and the occasional bird call cut through the tense quiet. Seeing one of these lone creatures is never guaranteed, given the vastness of the Amazon, but that doesn’t stop rush of knowing they could be stalking somewhere close.

It’s hard to fathom this jungle spans around 40 per cent of the entire South American continent and within its diverse depths are some 47 million people, 300 indigenous languages and 400 billion trees. Famously, it’s so biodiverse that on average we find a new species every other day. Little surprise, then, that exploring even a sliver of the Amazon could take a lifetime. Brazil’s north-west is home to 60 per cent of its 6.7 million sq km and 30 of its 53 ecosystems. Though the majority of the Amazon is tropical broadleaf forest, it also holds savannahs, coastal restinga are myriad ways to see such spectacles.

Trekking is a must for those who can, whether it be a half-day hike to scout for treetop toucans, or a multi-day, lodge-hopping journey through heavy jungle. Walking is the way to get up close to the flora and fauna, watchig through tree trunks for darting bodies or admiring the sun’s gild on foliage. With rivers crossing its heart, cruising the Amazon’s waterways offers immersion with hints of laid-back luxury. Passengers quickly become hawk-eyed macaws or the movement of red howler monkeys.

Underwater splendour Belize

Lying on Central America’s north-eastern edge, clasped between Mexico and Guatemala, Belize is only a touch larger than Wales, yet within its borders is a marbled swirl of ecosystems, creatures and culture. On land, Belize is carpeted in dense jungle, replete with the screech and hoot of hidden creatures. Among the tangled trees of Cockscomb Basin, the world’s only jaguar reserve (the elusive creatures are best glimpsed on night tours), hikers can long-forgotten research plane. To Cockscomb’s west, Mountain with cliff diving, mountain biking and wild swimming. Cayo’s jungle, where the sultury air is stippled with the flit of butterflies, is pockmarked with Mayan ruins: stone pyramids and temples, like the hulking Xunantunich, and underfoot caves like Actun Tunichil Muknal reveal teal pools and stalactites alongside the remains of human sacrifice. Belize's best, however, may lie beneath its glassy seas. Just off the palm-lined Caribbean coast is the world’s second largest barrier reef, rife with sea turtles, sharks, dolphins and even manatees. A renowned scuba and snorkelling region, its crowning glory is the Great Blue Hole, which can be explored from the skies above with Tropic Air tropicair.com or the depths below.

Epic landscapes Mongolia

Gazing out across the Gurvan Saikhan National Park – an ocean of camel-freckled grasslands disappearing into a horizon of mountains – it’s easy to believe Mongolia is the most sparsely populated country on the planet, sprawling across East Asia for some 1.5 million sq km with a population of 3.5 million. On the edge of the Gobi desert, Gurvan Saikhan is known for its altitudinous steppe, the cavernous valley of Yolyn Am, and the swirling, singing dunes of Khongoryn Els. Gobi camels, Siberian ibex, argali sheep, bearded vultures and snow leopard live here, and the Gobi itself is awash with tree-lined oases and rocky massifs. By day, visitors can explore the stone amphitheatre of Ikh Gazriin Chuluu and at sunset, the so-called Flaming Cliffs – red rock and dinosaur fossils – glow marigold. A mosaic of landscapes includes Alpine lakes and forests of the west’s Mongol Altai peaks, the wetlands and hills of the east, the cultural centre with Orkhon Valley and the ancient capital Kharkhorin. With a tiny transport network, the easiest option is to tour by car, bike or motorbike.