Peru Itinerary Help.
First, a short introduction - we're into archaoelogy & photography and we've always done our own planning. If we do any tours, it's a day tour from the location.

We have two friends coming with us, who will be joining us for the first 10 days of our two week trip. Therefore, the first part of our itinerary is mostly set - they want to see Machu Picchu, Cusco, and the rainforest. We will be in Peru at the end of May.

So far we have set up, fly into Cusco and transfer to Ollaytaytambo (in the early morning), spend a night there. Leave the next evening on a train to M.P., stay the night in Aguas Calientes, get up to see sunrise at M.P. and visit the site, and return to Cusco in the evening. Spend 3 nights and 2 full days in Cusco. Then, leave for Reserva Amazonica in Madre de Dios for two nights. At that point, our friends are going to take a flight back to Lima and head home.

That leaves us with so many options for our remaining 7 days. Obviously we could only choose one (or possibly two). We are definitely already considering spending another night in the rainforest. Another thing is that we'd like to really leave this open to see how we feel, but we don't know whether it will be easy to book flights/hotels on the fly in May.
1) More time in Cusco (a whole nother week might be pushing it)
2) Arequipa? But I'm afraid I can't figure out what's so great about the city, or whether Colca Canyon would really "wow" me.
3) Lake Titicaca - I'd love to go but my wife didn't like the lake we visited in CAmbodia and thinks it will be very similar.
4) Fly North to Trujillo and see Chan-Chan.
5) Head back to Lima and see maybe Nazca Lines and the Ballestas Islands and suchlike.

For people who have seen these various places, what things were unforgettable and unmissable? What things did you feel weren't worth the hype? And why?

As much as I love Cusco, another entire week there might be pushing things if you will already have spent a couple of days in the city.

Staying an extra day in Madre de Dios sounds like a plan. I don't think I would wait until I was there to make that decision; there might not be space at the lodge or on the planes. (There are just a few flights a day out of Puerto Maldonado, the nearest airport.) But I don't think you'd need to decide that now.

Arequipa is a lovely colonial city. very different than Cusco. Again, much as I like Cusco, I always have the feeling of being in a museum when I'm there. Arequipa is flatter, more spacious, brighter -- all the colonial buildings are whitewashed -- and it just has more the feel of being a real city to me. It's a nice contrast to Cusco.

I've seen claims Colca is "the deepest" canyon in the world, but others that say it's "one of the deepest" in the world. In any case, it's larger and deeper than the Grand Canyon.

As the highest navigable lake in the world, and with llamas and alpacas and indigenous culture all around, I would guess Lake Titicaca will be nothing like Cambodia. (Been to Lake Titicaca, but never to Cambodia.)

If archaeology is of intersest to you, you'd like Chan Chan, but Trujillo isn't exactly in the area where you'll be. Arequipa and/or Lake Titicaca fit better into a Cusco-Sacred Valley-MP-Madre de Dios trip.

Hi!
Lake Titicaca and surroundings is marvelous! If possible, stay at one of the fancy hotels by the lake and take the day trip to Isla Taquile, an amazing island where locals live with their old traditions.
Haven´t been to Colca Canyon yet, but the nice thing about the place is that the little old villages surrounding are also beautiful.

Other magnificient places to visit are KUELAP in the city of Chachapoyas (take a plane from Lima or a bus from Chiclayo) and Chavin, in Huaraz. You could even go to both places if you head up north after your Cuzco and Puerto Maldonado trip.

Both Kuelap and Chavin de Huantar seemed really hard to get to - but Kuelap is high on my list of one-day-must-sees.

I didn't know there was an airport there?

Chachapoyas has an airport and it was used only for charter flights, but I am almost sure one of the small Peruvian airlines now offer a regular flight. Let me find out, cause I´ve read about it somewhere!

Nazca is also a good choice. A bus from Lima to Nazca takes about 5 hours and there are several hotels to stay at. You can then go to Paracas and visit the Islas Ballestas - a 3 hour trip by boat. BUT.... I wouldn´t discard Puno... I really enjoyed it!