On the picture to the right, you can see how the younger cone arises from the older caldera floor. The caldera is breached to the east, where there is access into the caldera filled with large boulders, which are overgrown with small bushes and plants. The crater on top of the cone is wide and deep and part of the rim was destroyed by the huge eruption of November 3rd, 2002. Lava descends into the caldera when stronger explosions occur.

El Reventador had a major eruption on Sunday, November 3rd after 35 years of slumbering peacefully with no visible sign of activity. This eruption with a vertical ash column, reaching a height of 15 kilometer and ejection of hot pyroclastic material of 400° C+ and lava flow down the flanks, surprised everybody with no advanced warning at all. The eruptive process started early in the morning and the huge explosion occurred at around 9 am. Ashes covered in the following hours an area in the Amazon and Andes of 20 000 square kilometers from the border to Colombia and south to Cuenca. Ashes began to fall on Quito, 90 km west of it, at around 2 pm and continuing on into the night, covering the entire city with up to one centimeter of a fine ash layer. Mud flows reached the main road connecting Quito with Lago Agrio and blocking the access to the nearby villages, where around 1500 people left the area, leaving behind their belongings and animals. No victims were reported yet but 5 cm of ash has covered the surrounding areas making the pasture inedible for the cattle. The oil pipeline, which connects the oil producing areas in the Amazon with the Pacific coast, still is functioning as most of it is underground passing the volcano. In Quito, the international airport was closed and classes suspended for a week. Dusty conditions prevailed for the following days and the sun was blocked out by the fine ash particles suspended in the air. November 4th was declared a work free day for people so they could start to clean the ashes off their yards and roofs.