Riding at Altitude: Horses in the High Andes

Perol Chico’s Sacred Valley Ride is a true high-altitude journey, among the highest offered in the world of equestrian travel. Riding begins at approximately 9,200 ft (2,800 m) and gradually ascends to mountain passes reaching 14,270 ft (4,350 m) above sea level.

In this article, we aim to explain the physiological impact of altitude on horses, and why riding at these elevations requires time, understanding, and respect for the animal.

Regardless of fitness or conditioning, horses do not perform at high altitude in the same way they do at sea level. The effects of altitude begin to appear above 5,000 ft (1,524 m) and become increasingly noticeable above 7,000 ft (2,143 m). At higher elevations, air pressure is lower and fewer oxygen molecules are available with each breath. For every 1,000 ft (305 m) gained in altitude, the oxygen available in the air decreases by approximately 3%. At around 14,000 ft, this results in roughly 40% less oxygen per breath compared to sea level.

To compensate, the horse’s body initiates several adaptive mechanisms. The most immediate response is an increase in respiration rate, allowing more oxygen to enter the lungs. Heart rate also rises to circulate oxygenated blood more efficiently throughout the body. Over time, the body begins to produce additional red blood cells and capillaries, improving oxygen transport. This acclimatisation process typically takes four to seven days, after which a horse living at altitude may have up to 50% more red blood cells than a horse at sea level.

To protect vital organs such as the brain, heart, and lungs, blood flow is prioritised toward these systems, while supply to other organs—particularly the digestive system—is reduced. This redistribution can lead to temporary side effects such as headaches or mild digestive upset. One of the most significant challenges at altitude, however, is dehydration. Due to dry air and increased respiration, horses above 6,000 ft can lose nearly twice as much moisture through breathing and sweating as they would at sea level.

Our horses live year-round at an altitude of 9,200 ft (2,800 m) and are naturally adapted to these conditions. Even so, ascending to higher elevations places additional demands on their bodies. Through years of experience—and learning along the way—we have found it essential to allow two to three days of gradual acclimatisation during longer rides before asking our horses to work at their full capacity.

Interestingly, our horses often feel stronger and fitter during the later stages of a journey than during the first days. This is not surprising when one understands the physiological adjustments required to move through such demanding terrain at extreme altitude.

Occasionally, riders arrive with expectations shaped by riding at lower elevations—hoping for speed or extended gallops. At these heights, however, progress is measured differently. Reaching high mountain passes with a rider aboard requires patience, balance, and considerable effort from the horse.

We are immensely proud of our horses. Their strength, generosity, and willingness in difficult mountain terrain never cease to impress us. Adapted to the Andes, they embody endurance rather than speed, and heart rather than force—qualities that define true high-altitude riding.

Eduard van Brunschot