holiday lens for trekking in Peru

We were there in April: Lima, Cuzco, Sacred Valley and Machu Picchu, and we loved it. I used a Nikkor 20mm f2.8 AiS for about 90% of my shots ,for both landscapes and urban street shooting (using zone focusing) on my D7000. You're definitely going to need something wide for the landscapes. It's small and light and I am very happy with the image quality. Have fun!