Ecuador is world-renowned for its incredible biodiversity and spectacular mountain landscapes, but there's something else that defines the geological character of this Andean country: its volcanoes. With more than 80 registered volcanic formations, many of which are active or potentially active, Ecuador ranks as one of the countries with the highest volcanic density in the world.
From the majestic silhouette of Chimborazo to the constant eruptions of Sangay and El Reventador, Ecuador is a natural laboratory for volcanology. Below, we present a comprehensive geological tour of Ecuador's volcanoes, including snow-capped volcanoes, active volcanoes, and those now dormant, which also tell their part of the country's geological history.
The Avenue of the Volcanoes: an Andean corridor of fire
The so-called "Avenue of the Volcanoes" is a volcanic strip that crosses Ecuador from north to south, following the Andes Mountains. This impressive mountain range is made up of active, dormant, and snow-capped volcanoes, which stand like silent or roaring sentinels across the country.
Among the most emblematic volcanoes of this corridor are the Cotopaxi, Chimborazo, Cayambe, Tungurahua and El Altar. All of them play an important role in both the mountain ecosystem and the culture and spirituality of local indigenous communities.
In addition to the spectacular scenery they offer, these volcanic giants also attract the attention of scientists due to their constant activity and documented geological history. The fact that many are covered by glaciers makes Ecuador one of the few tropical countries with active snow-capped mountains.
Classification of volcanoes: active, inactive, and potentially active
Ecuadorian volcanoes have been classified into different categories according to their level of activity and geological evidence. According to the Geophysical Institute of the National Polytechnic School, three main categories are identified: active, potentially active, and extinct (or inactive).
An active volcano is one that has had documented eruptions in historical times, that is, after the arrival of the Spanish in the 16th century.. Well-known examples are Cotopaxi, Reventador, Sangay, Tungurahua and Guagua Pichincha.
Potentially active volcanoes are those that have not had recent eruptions, but have geological records of activity in the last 11.800 years (Holocene period). This includes volcanoes such as Cerro Negro and Antisana.
Finally, extinct volcanoes have not shown eruptive activity in modern times nor recent geological evidence. They have a highly eroded morphology and are covered by thick soils, as is the case of Pasochoa or Imbabura.
Highest volcanoes in Ecuador
The altitude of Ecuador's volcanoes is impressive, making the country a prime destination for mountaineers and geological explorers. Chimborazo Volcano takes the top spot at 6.263 meters, and interestingly, due to the Earth's bulging shape at the equator, its summit is the furthest point from the planet's center.
It is followed by Cotopaxi (5.897 m), which is also one of the highest active volcanoes in the world, Cayambe (5.790 m), Antisana (5.758 m) and El Altar (5.319 m). All of them are part of the Eastern and Western Andes mountain ranges and are partially covered by eternal snow, which feeds glacial rivers essential for water supply.
Due to their altitude and beauty, these volcanoes are national icons and are part of several protected areas and national parks.
Active and erupting volcanoes: constant monitoring
According to data from the Geophysical Institute, Ecuador currently has 17 volcanoes considered potentially active, some of which are constantly erupting. Among the most notable are Reventador, Sangay, Tungurahua, Guagua Pichincha and Cotopaxi.
Sangay, for example, has had almost continuous eruptive activity for more than six decades. Located in Morona Santiago, this stratovolcano has had significant impacts on the Amazon region due to its constant emissions of gases and ash.
Another tireless colossus is Reventador, which has been erupting since 2002. Its last major eruption produced an ash column 17 km high and caused the closure of Quito's airport, affecting the country's oil infrastructure.
Currently, Reventador continues to produce daily explosions, ash emissions, lava flows, and pyroclastic flows, as well as thermal anomalies detected by satellites and thermal imaging cameras. Rifts have been identified on its flanks, where hot material descends, potentially generating lahars in the event of heavy rains.
Volcanic monitoring includes the use of seismometers, visible and thermal cameras, gas sensors such as sulfur dioxide, and satellite image analysis. This entire monitoring system makes it possible to anticipate potentially dangerous events and protect nearby populations.
Dormant volcanoes and their geological legacy
Most of Ecuador's volcanoes are considered inactive or extinct, which doesn't mean they're not of geological or tourist importance. Many are natural destinations visited by thousands of people each year for their lagoons, biodiversity, and unique volcanic landscapes.
Pululahua Volcano, for example, is considered inactive, but its crater has become a fertile, inhabited caldera thanks to the volcanic soil. The area is classified as a Geobotanical Reserve.
The Quilotoa volcano, with its impressive turquoise lagoon, is another example of a dormant volcano that dazzles with its beauty. Its last eruption dates back to the 18th century, and today you can hike around its crater.
Others, such as Ilaló, Pasochoa, Mojanda, and Soche, are part of the Andean landscape and have left traces of their volcanic past in the form of eroded valleys, crater lakes, and mineral-rich soils.
The volcanoes of the Galapagos Islands
Not everything is on the continent. The Galapagos Islands are also home to active and dormant volcanoes, part of a unique geodynamic system. Here, volcanism is not linked to subduction, but to hot spots, such as the one that gave rise to the archipelago.
Among the best known are Wolf Volcano (1.710 m), Cerro Azul (1.640 m), Sierra Negra (1.124 m) and the Summit on Fernandina Island, which had its last eruption in 2020.
These volcanoes remain active and are monitored by satellites and remote sensors due to their difficult access. Recent eruptions in the region have left spectacular images of the lava flow reaching the sea.
Monitoring in the Galapagos is limited by remoteness and logistics, but remains critical due to the impact it can have on the archipelago's unique biodiversity.
Ecuador is a country shaped by the internal fire of the Earth. Its volcanoes are not only a geological spectacle, but also a constant reminder of the planet's dynamism. From active giants like Reventador and Sangay, to majestic snow-capped peaks like Chimborazo and dormant volcanoes like Pululahua, the Andean country offers a unique mosaic of volcanic landscapes, natural hazards, and scientific opportunities. Monitoring and studying these giants remains critical to the safety and sustainability of the populations that live alongside them.
