Well, take this for what it's worth, because I am going in May so I am planning, but 6 days is plenty of time:

Day 1: Fly to Cuzco; tour Cuzco; stay Cuzco
Day 2: Tour Sacred Valley; stay in Ollantaytambo
Day 3: Train to Agua Calientes; tour MP; stay in AC or train back to Ollan or Cuzco
Day 4: Tour Cuzco or more of SV
Day 5: Fly back to Lima
Day 6: Fly home

I didn't know if the 6 days meant you are flying internationally on the 6th day. Either way, you should fly back to Lima a day before your international flight, in case there are delays/weather issues.

Many people do MP in a day, some take 2. It's the travel time that eats ups days, but there is plenty to see in SV and Cuzco to fill out your time.

Pretty good itinerary. However to minimize altitude headache and downtime, go straight to a hotel in the Sacred Valley and not plan on heavy sightseeing. On Day 4 you can do Cusco.

Six days is entirely doable but I have to disagree with with the previous poster that " 6 days is plenty of time" . Flying into Cusco which is above altitude at which altitude sickness can kick in, means that most ( but not all) people will be affected to some degree. I was affected quite badly with bad headaches, breathlessness etc., but my wife, not so much. Age, sex and fitness does not determine who will or won't be affected. Your best bet would be to go directly from the airport to Ollantaytambo. a day there will aid acclimatisation and you could explore explore the SV from there and get the train to Aquas Calientes for an overnight and to visit Macchu Picchu. You could then return to Ollantaytambo by train and then to Cusco by car exploring along the way. moray, maras and Chinchero are all worth a look. Pisac should also be on your list ( I preferred it to MP!) you would then end up in Cusco and its higher altitude, acclimatised and ready to explore.

A Sacred Valley Tour will (should) include Pisac.

A friend of mine who is native to the Andes told me the best way to minimize altitude sickness is to eat nothing (maybe a little soup at night) and do as little as possible the first day in the mountains. Drink coca leaf tea and water. I also found last trip that glucosamine seems to help. But what really helped was taking a bus to Huaraz rather than flying direct to Cusco.

Is Ollantaytambo really that much lower than Cusco that altitude sickness is not so severe there?

Ollantaytambo is approximately 2,000 feet lower in elevation, at about 9,160 feet (2,792 meters). Cusco is over 11,100 feet (approx 3400 meters at the Plaza de Armas).

So, do you think 2,000 feet is enough to make a difference? There is no way to predict any one persons response to suddenly arriving at high altitude (over twice as high as Denver, btw). However, 3,000 meters is the point at which many people get more significant symptoms including headache and nausea, and doctors start to suggest Diamox.

I can only say that I don't have a headache when I sleep in Ollantaytambo, but I do when I go to Cusco for the first few nights...even after a few nights at a lower elevation.

Much better to spend the first couple of days in Olly, the sacred valley has loads to stuff to see. Then take the train to Aquas Calientes/MP, coming to Cusco on your return. Personally, we didn't have a problem with altitude sickness except for some breathlessness even though we stayed first at Cusco and the sacred valley only later, but it's better to be careful. Don't do too much the first day, drink a lot of coca tea, stay hydrated and you should be fine. Six days isn't a lot for Peru, make the most of it

Here is a link to the UK NHS website which explains altitude issues very well and provides some sound advice http://www.fitfortravel.nhs.uk/advice/advice-for-travellers/altitude-and-travel.aspx

Mlgb is spot on re 3000m being the magic level for altitude to kick in. I found coca tea helped a little, chewing coa leaves was much more effective though! I am consider consulting my doc re using Diamox on my next trip as we plan on going to some pretty high altitudes. As far as glucosamine is concerned dad, if it worked for you then great but I have never heard of this before. Did you tke it on recommedation of a doctor? I thought it was intended for joint problems?

Like many others, because mass market tours start in Cusco, I had assumed that Machu Picchu was higher and I needed time to sleep in Cusco before visiting MP by train. But after visiting Fodors I learned that this is a misconception.

For some people, Cusco will cause symptoms, ie the headache, nauseau, perhaps dizziness, which usually go away in 24-48 hours whether you take Diamox or not. If you have only 6 days, that can knock a big chunk out of your sightseeing. If you have a few weeks, spending a day or two in bed doesn't matter as much.

I have never taken the Diamox, although I had the pills with me when I went to Lake Titicaca, La Paz, and Bolivia. After the first few nights at Yanque (about the same elevation as Cusco), I was good to go.

Crellston Re Glucosamine--first time around, I went to a pharmacy in Cusco to see if they could give me something for a headache--I think this was after going to and returning from MP. They gave me glucosamine sulfate and it did make me feel better. Later on the trip, I took a tour to Colca Canyon and the guide stopped at a pharmacy on the way in case someone wanted to buy something for the altitude. I didn't buy anything but those who did got glucosamine sulfate.

Five years later, after I'd begun taking glucosamine for joint pain, didn't have any problems anywhere--other than shortness of breath in Cusco. But as noted above, first out of Lima was a bus to Huaraz and I believe the slow ascent helped.

The fact that Huaraz is about 1,000 feet lower than Cusco may have helped also.

Thank you for the helpful tips. On all accounts the high altitude is the main issue so we will have to get more days in and take our time in ascending.

Can anyone recommend a tour company for sightseeing.I was told intrepid or tempo?

We just returned from Peru and did the Inca trail. We also visited Puno and Titicaca with 2 nights of homestay. Our agency p^lanned for the porters and all transfers and hoemstays. All was very good and the communication never lacked. I will use them again for Columbia and Boliva. The agency is Transandes and I would highly recommend them.

Perhaps my TR will help:

http://www.fodors.com/community/south-america/dcds-trip-to-peru-what-a-beautiful-country.cfm