I´m planning to go Peru with my wife and would like to have an "off the beaten path" experience.
That's exciting! You will LOVE Peru! One thing you must do if you want off the beaten path, is hike to Choquequirao. I never went, but I met a woman who traveled there and she said the experience was amazing--better than her trip to Machu Picchu. She and her group were the only ones there; on top of that, there are plans for a cable car to be built to Choquequirao so tourists can get there more easily--better get there before it's commercialized.
Here's some info about the trek: http://www.theguardian.com/travel/2014/nov/01/peru-choquequirao-inca-ruins-trek
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