Ingredients: Waterproof boots; IGM maps for Papallacta, Sincholagua, Cotopaxi, and perhaps Laguna de Mica; the itinerary from "Climbing and Hiking in Ecuador"; pathfinding skills; grit.
Trek del Cóndor was my first trek, I survived, and it was beautiful!
From Río Tambo, 4km before Papallacta, the first day's hike is a moderate 4 hours or so, arriving at lovely Laguna Volcán to camp, in sight of an amazing ancient lava flow frozen in time, which you can explore if you arrive early.
Day 2 starts with a grueling 4-5 hour uphill push, the hardest segment of the trek. The afternoon, though, rewards you with stunning views of volcano Antisana and the surrounding highlands, and easy terrain. Actually, since this was in December, late dry season, we crossed the swamp easily, covering Days 2 and 3 just in the second afternoon. We had to: the streams mentioned early in Day 3 of the itinerary were stagnant ponds and we had no water. We camped by a river somewhere near the Hacienda Hito, which we never saw (we had wandered a little too north).
Day 3 (itinerary Day 4) appeared on the map to be one uphill and a lot of cross country, a sweeping valley leading to Volcán Sincholagua. It was actually up and down a series of hills, including some awkward grasses. Wild horse country. We had occasional peeks at Antisana behind, though Sincholagua was hidden behind a veil of cloud - we only guessed that the rock ahead was the beast. The valley narrows into marshland leading to the base of Sincholagua, who finally showed her Mordor-like glory of red and black rock.
The morning climb past Sincholagua was difficult - misty, windy, and the way obscured by thick fog. Soon, though, the sky cleared and the trek was cross-country (marshy) and downhill, with bleak Sincholagua behind and the breathtaking Cotopaxi before. Easy grassland past herds of llama gets you to the road, where you can proceed to the refuge at Cotopaxi, the lake of Limpiopunga, or back to civilization.
There was a locked gate in the road (easily climbed) but no signs of anyone. I hear the gate is always locked.
Don't dream of hitchhiking on the jeep track mentioned in the itinerary, though - you'll wait weeks. You need to get close to Cotopaxi to find a ride.
All in all, an amazing journey through páramo highlands. A beginner can do it, but you MUST go with maps and someone experienced. The itinerary is good, but even the experienced get lost here.