Between August 11 and 29, the mountainous area of Antuco, in the Biobío Region, is the setting for the Combined Exercise “Southern Vanguard 2025,” which brings together more than 500 mountain troops from the Armies of Chile, the United States, Argentina, and Peru. The mission is clear: to strengthen interoperability and test combat and survival capabilities in one of the most demanding environments for any force—the winter mountain.
The activity, held for the second time in Chilean territory, was inaugurated at Mountain Detachment No. 17 “Los Ángeles” with a ceremony led by Major General Pedro Varela, alongside military authorities from the participating nations.
Led by the Chilean Army’s III Mountain Division, the exercise is structured in three phases. The first involves individual and collective instruction in snow movement, survival, the use of skis and snowshoes, and high-altitude combat techniques. Next, the Integrated Training Phase (FIT) aims to standardize multinational procedures and communications. The cycle concludes with the Final Field Exercise (FTX), which simulates defensive and offensive operations, high-altitude resupply, and medical evacuations under extreme conditions.
The forces on the ground include Mountain Detachment No. 17 and Chilean specialists in high-altitude logistics; the U.S. Army’s 10th Mountain Division; the “Cazadores 6” Company of the Argentine Army’s VI Mountain Brigade; and a squad from the Peruvian Army’s Mountain School.
“This is not just about training, but about building relationships, learning about our cultures, and preparing to operate together in any environment,” emphasized Brigadier General Claudio Mardones Peterman, Commander-in-Chief of the III Mountain Division and General Director of the Exercise.
From the U.S. side, Brigadier General Michael Eastridge, Deputy Commanding General of United States Army South, stated that Southern Vanguard “will test our ability to integrate seamlessly, strengthen the confidence of our young leaders, and forge bonds of respect and cooperation essential in times of uncertainty.”
A combat laboratory in extreme climates
Operating in the winter mountains is one of the most complex tasks for any land force. Extreme cold, deep snow, rugged terrain, and reduced oxygen levels decrease physical and mental performance. Here, human or technical error can be as lethal as the enemy.
– Physiological challenges
- Hypoxia and hypothermia affect endurance and decision-making capacity.
- Acclimatization and mental resilience are as important as technical skill.
– Logistical challenges
- Requires specialized transportation: pack mules, sleds, snowmobiles, and high-altitude helicopters.
- High-altitude resupply is limited and costly in both time and resources.
-Tactical challenges
- Mobility is reduced, and progress depends on precise terrain reading.
- Combined-arms coordination at altitude requires reliable communications and unified protocols.
Southern Vanguard 2025 is, in practice, an operational rehearsal for real situations in which forces from different nations must act as a single unit. The lessons learned here apply to both combat scenarios and rescue missions, humanitarian assistance, and combined operations in remote areas.
In the mountains, interoperability ceases to be a concept and becomes a tangible capability. And in Antuco, where nature offers no margin for error, that capability is trained, tested, and consolidated.
*Original text by: Rodolfo Neira Gachelin
Photographs courtesy of the Chilean Army.
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