My girlfriend and I are coming to Peru in September to hike the Salkantay Trek and visit Machu Picchu. We've already arranged all that with Alpaca Expeditions. We are going to be picked up in Cusco early Monday morning to start our 5 day, 4 night hike. We are taking a red eye flight that lands in Lima at 7 AM on Friday. Originally, we had planned to spend the day and night in Lima and fly to Cusco early on Saturday, but we are now thinking it would be better to have an extra night's sleep in Cusco to make it at least 3 nights and 2 days to acclimatize instead of just 2 nights. We are healthy and in our late twenties, but we live at sea level and are not used to the altitude. We really hoped to see Lima, because realistically we don't have any expectations to return to Peru soon. What is your advice on the following options: Spend Friday in Lima and fly to Cusco on Saturday morning as originally planned. (2 nights, nearly 48 hours to acclimatize) Book a long (8-10+ hr) layover through Lima and travel into the city for a few hours to see some of Miraflores (3 nights, 2 days to acclimatize) Book a shorter layover (4-6 hr) and stay in the airport (3 nights, 2+ days to acclimatize)