Leave the hut Nuevos Horizontes and aim to go to the base of the north face of Iliniza Sur, as if going to the Normal Route.
The Rampa Route is the notorious ramp that drops from the Ambato (north or lower ) Summit, in the middle of this face. This used to be the normal route up to the early 1990s, but glacier retreat has made the route increasingly harder.
Climb the ice/snow ramp (sections of 80 degrees, sustained) and then head up and left to the rock band on top. The rock can be climbed Yosemite 5.5 to 5.7, being easier on the right side. Also, it is possible to climb the rock band on the very left, as the normal route used to go, getting on the Ambato (lower) summit.
After you climb the rock, traverse the summit ridge towards the left side, leading to the main summit. You will pass a rocky formation called "El Hongo" and then you will gain the main summit. Be careful with the summit cornise.
Descent is done via the normal route. Do not count on finding the normal route easily, as the main summit is cornised and steep. The Normal Route will connect to the summit from the left side. Check the route from the bottom to be sure you know the way down.
This route calls for 2 ice axes, better ice tools than regular piolets. Ice screws are necessary to protect the ice piches, and a couple of snow pickets. Be sure to have good crampons for front pointing, as this is a very tiring technique at this height.
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