I got it. It is about a 4 hour train ride from Cuzco to Aguas Calientes. I read one persons review, they said they left about 6am to get the train from Cuzco to AC, then took the 20min bus to MP. They then toured MP, and caught the train back from AC to Cuzco at 1 pm. So, if you were really strapped for time, you could fly from Lima to Cuzco and spend the night in Cuzco (1 night), get up take the early train to MP, see MP and take the train back to Cuzco that day, stay in again in Cuzco, (2 nights), fly back from Cuzco to Lima next day on day 3. Then fly from Lima to your cruise. I don't know what tour operators to take for that itinerary. You probably could find a tour on the internet. We took a company called Gap Adventures, they were recommended from National Geoghraphic Travel magazine. We booked a tour with them for the Galapagos Islands and MP. We first sailed around the Islands for 7 nights, in a tiny boat, then flew to Peru and hiked the Inca Trail for 4 days. Gap Adventures has a awesome website. Check it out, maybe you could do a tour with them to hike the Inca Trail, since you'd love to do that. But then again, since you'll be down there in SA, it'd be easier just to see MP before your cruise.