Find me a cheap flight and a cheap hostel, and I'll go anywhere.
This past May, we squeezed in a week of parading through Peru. Our trip started with an airport overnighter in Lima on 5/3, followed by the first flight into Cusco. We arrived at Cusco shortly after sunrise, and barely surviving the altitude, made it into our hostel (hostel Pariwana).
After exploring Cusco, shuffling through the culture shock that is a (huge) Peruvian mountain town, and hitting the bars with their fake western "happy hours," we took, again, the first train in the AM to Aguas Calientes, the mountain town that is the hub of Machu Picchu. The hangover presented to us by Pariwana did not fare well, but made for some excellent napping.
We arrived in Aguas rather early. Nightlife is virtually non-existent, but we did check out the "hot springs" and a waterfall. Absolutely visit the waterfall; we met a local botanist who lived below it and grew wild orchids. The hot springs were more like warm pools, ultimately giving one of us Machu's revenge.
Machu Piccu is, of course, Machu Piccu. There's a reason millions(?) of people visit it every year. Don't be a turd; do the hike. It's not that long, and when you're finally ready to give up you're at the top. You'll definitely feel it was earned, and the experience will be that much more rewarding. There's a passport stamp at the top as well, and the food is ridiculously expensive. Besides, the views on the way up are breathtaking.
We didn't buy a tour guide, but we did buy a book at the top which taught us a lot of things that I don't remember. It did make the ruins a little more interesting though.
You're also not "supposed" to feed the Llamas.
After Machu, we took a train to Ollanytambo. We found Ollantay absurdly touristy, so we briefly got lunch before haggling for a taxi to Pisac.
I felt like Pisac showed us a more genuine view of the culture in the Peruvian mountains. We found a market, ate a local meal for 5 soles (<$2), and took the most cramped bus that night down to Cusco.
We didn't get enough of Cusco in one day, and you totally can't. This time we did an ATV tour which took us to a huge mountain lake and some salt flats, through winding village roads, and into some epic valleys.
The next day we took a less early flight into Lima, met some mutual friends, and nursed our hangovers in Miraflores. The sand-boarding trip took us about 30 minutes outside of Lima into an entirely different geography, where we got stuck and incredibly sun burnt.
Would I do it again? Absolutely. My only regret is that we only had a week. We took a red eye out of Lima on 5/10 at 1 AM. Over 3500 km in one week, with no sleep, too many hangovers, and no missed flights. Take me back.
Buy your pass to Machu as early as you can. They sell out and essentially cannot be purchased in Aguas:
Be mindful of your food, and even more mindful of your water. BRING A WATER FILTER.
Hostel Pariwana, Cusco,
Supertramp hostel, Aguas
Wild Rover, Cusco (you will not survive this bar)
Hostel Pariwana, Miraflores, Lima.
Ask around for taxi prices and negotiate them. Don't let them overcharge you. Don't let them charge you for service tax at restaurants.
Bring your friends and don't hesitate to try something new.