In 1852, the American artist Frederic Edwin Church read Alexander von Humboldt’s account of his travels in central America, and decided to rise to Humboldt’s challenge to depict the ‘physiognomy’ of the Andes mountains. The following year he travelled to Columbia and Ecuador with the businessman Cyrus West Field, who bankrolled their trip in the hope that he could use Church’s paintings to promote his own local business ventures. They based themselves in Quito, travelling from there to awe-inspiring views of mountains and volcanoes.

The Andes is one of the world’s greatest mountain ranges: the longest continental mountain range of them all, amounting to nearly nine thousand kilometres (over five-and-a-half thousand miles) in length, and joining up with the Rocky Mountains and others to form the western rim of the Americas. Yet until the twentieth century, Church was one of very few who painted its peaks.

Church painted this view of what’s thought to be Cayambe in Ecuador in August or September 1853, in pencil and gouache.

On his return to his studio in New York, Church turned those hundreds of sketches and drawings into larger finished paintings, in this case one of his many views of Cotopaxi (1855) in Ecuador. As was conventional at the time, these are highly finished, with no evidence of brushwork and a smooth paint surface.

Cotopaxi is an active volcano to the south of the city of Quito, and rises to a height of almost six thousand metres (nearly twenty thousand feet). Its summit is a huge crater, on top of one of the few glaciers on an equatorial mountain. Just over twenty years later, its entire ice cap was melted by the flows from one of its most violent recorded eruptions. Humboldt tried to reach its summit in 1802, but it wasn’t reached until 1873, and in 1880, the famous alpinist Edward Whymper completed the third recorded ascent, with two Italian guides.

Church’s other versions of this motif weren’t as peaceful: that of 1862, commissioned by James Lenox, shows rugged waterfalls in the foreground, a barren rocky plain, and the volcano itself ejecting a high plume of smoke and ash. All this is lit by a blood-red sun, sitting low in the sky. This was to enable Church’s painting to serve as a pendant to one of Lenox’s other paintings, Turner’s dramatic Staffa, Fingal’s Cave (1832).

He returned to central America in 1857 with the artist Louis Rémy Mignot and added hundreds more drawings and sketches to his collection.

Cross in the Wilderness, which he painted later that year, is one of the earlier works to result from his second visit. This wilderness is unpopulated, devoid of figures or other signs of human presence.

His rather larger oil sketch of Mount Chimborazo in Ecuador is rich in painstaking detail for a study which was never intended to be viewed by others. In comparison to his studio works, though, it’s full of fine gestural marks with some quite painterly passages. Mount Chimborazo rises to 6,263 metres (20,548 feet), and is Ecuador’s highest mountain. Although another volcano, it’s now thought to be inactive, with its last eruption in about 550 CE. During his expedition to South America in 1802, Humboldt had to abandon an attempt on its summit due to altitude sickness. It wasn’t climbed successfully until 1880, when Edward Whymper and two Italian guides became the first Europeans to reach a summit above 6,100 metres (20,000 feet).

He may have painted this atmospheric view of mountains in the moonlight during either of his visits to Colombia and Ecuador.

Church’s elevation to fame came on 29 April 1859, when the first of more than twelve thousand people walked into the Studio Building on West 10th Street in New York City, to stand in awe and amazement in front of his huge painting, The Heart of the Andes (1859). For many, its dramatic view of a densely-vegetated plain with its backdrop of snow-capped mountains wasn’t its most impressive feature: it was the painting’s meticulous, almost overwhelming detail.

Tucked away among the brightly-coloured birds and rich plant life, at the very heart of The Heart of the Andes, is a cross, with two figures by it. Dressed as locals, one sits, facing the cross, while the other stands just behind the seated figure, looking in the same direction. The cross is made simply of wood, and appears to have been decorated with a floral garland. It is partly obscured by the luxuriant wayside plants.

Over its five square metres of canvas, these are the only visible humans.

They’re part of a complex passage. The cross stands just off a path winding its way past a dead tree-trunk, seen at the left here, on which the artist has ‘carved’ the year and his name. The path then curves to the left, along the bottom of a small gully, where it disappears into the trees and undergrowth.

On the other side of the river, to the right, is a small mission-like settlement. Facing the viewer is the tower and broad frontage of a church, with its large double wooden doors. Beyond and around is the enormity of nature: open plain with scattered trees, then rising ground to the first hills, and many miles distant the soaring white peaks of the Andes proper. Viewers were recommended to bring opera glasses in order to see the details through the crowd.

Church’s paintings after The Heart of the Andes continued to include figures. Beneath the spectacular double rainbow of Rainy Season in the Tropics (1866), they add a dash of contrasting colour. As shown in the detail below, there’s even more on the move in this painting. Splashing through a rocky stream is a small train of pack animals with two drivers, who have paused for a moment to adjust a load.

Spanning much of the foreground of Church’s Pichincha (1867) is a suspended bridge, one end glowing in the early morning light. Just over half way across, a woman wearing a brilliant red blouse is riding side-saddle on a mule, which is picking its way slowly across the thin logs which form the walkway of the bridge. At the left end is another mounted figure, who has just completed that frightening crossing.

Pichincha is another volcano in Ecuador, visited by Humboldt in 1802, and even closer to Quito. Its two peaks are around 4,700 metres (15,500 feet) in elevation.

Church wasn’t the only painter of the Andes in the nineteenth century. The Venezuelan artist Arturo Michelena painted a grimmer reality.

Michelena’s Crossing the Andes (1889) shows the harsh conditions experienced by an army unit operating at altitude and in bitter weather in the Andes. It was perhaps his response to similar paintings that he had seen when he was making his name in Paris, showing the Alpine and winter campaigns of Napoleon.